6th International Conference on New Frontiers in Physics (ICNFP 2017)
16 August: Arrival day, 17 August, 8h30: Start of Lectures, 18 August, 8:30: Opening of the main plenary session of ICNFP 2017, 26 August, 13h00: Closing of the main plenary session of ICNFP 2017. 27-29 August: Workshop on "Future of Fundamental Physics". 29 August 13h00: Closing of ICNFP 2017. Departure day.
The International Conference on New Frontiers in Physics aims to promote scientific exchange and development of novel ideas in science with a particular accent in interdisciplinarity. The conference will bring together worldwide experts and promising young scientists working on experimental and theoretical aspects of particle, nuclear, heavy ion and astro-particle physics and cosmology, with colleagues from other disciplines, for example solid state physics, mathematics, mathematical physics, quantum optics and other.
This year several special scientific events will be organized, among which: a session dedicated to " QCD - from the vacuum to finite temperatures ", and mini-workshops on " New Discoveries in High Energy Physics ", " Continuous Variables and Relativistic Quantum Information", " Quantum Foundations and Quantum Information ", " Astrophysics, Cosmology and Gravity ", " Physics at FAIR-NICA-SPS-BES RHIC energies ", " Correlations and Fluctuations in Relativistic Heavy Ion Collisions", " Exotic Hadrons " and other (see the menu in left side of main webpage).
The conference will be hosted in the Conference Center of the Orthodox Academy of Creta (OAC), an exceptionally beautiful location only a few meters from the mediteranean sea.
TBA
Central to the solution of the infrared catastrophe of quantum electrodynamics and perturbative quantum gravity is the idea that detection apparratus inevitably have limited resolution and, in any scattering processs, an infinite number of arbitrarily soft photons and gravitons are produced and escape detection. Photons and gravitons have polarizations and momenta and one might suspect that those which escape can carry away a significant amount of information. In this talk, I will examine the question as to the quantity of this information loss, its consequences and suggestions for experimental tests of the theoretical ideas, including whether precision interference experiments could see quantum gravitational effects.
The origin of Baryon Asymmetry of the Universe is one of the major questions in Particle Physics and Cosmology. We reconsider generation of the baryon asymmetry in the non-minimal split Supersymmetry model with an additional singlet superfield in the Higgs sector. We find that successful baryogenesis during the first order electroweak phase transition is possible within phenomenologically viable part of the model parameter space. We discuss several phenomenological consequences of this scenario, namely, predictions for the electric dipole moments of electron and neutron and collider signatures of light charginos and neutralinos. We also point out a possibility to probe the model with the next generation of gravitational interferometers, which may observe the gravitational waves produced at the Electroweak phase transition.
I discuss tensions between numerical simulations based on $Lambda$CDM cosmology and observations at galactic scales (Small-scale Cosmology ``Crisis'') and then proceed to review ways of alleviating them, including the inclusion of self-interacting dark matter. As a specific model of such dark matter, I discuss minimal extensions of the standard model, involving right handed (Majorana) neutrinos, which however are assumed to be self-interacting via vector potentials in the dark sector. The galactic scale phenomenology of such a model, and ways of resolving the aforementioned issues in small-scale cosmology, are discussed. It is found that consistency with observations regarding galactic halo-core structure in several galaxies, including the Milky Way, requires a mass for the right-handed neutrino dark matter in the O(50) keV range, with a self interaction coupling (at low (keV) energies) about eight orders of magntidude stronger than the weak interaction Fermi coupling in the corresponding range of energies. This mass range of right-handed neutrinos is in a remarkable coincidence with that for the lightest right-handed Majorana neutrino in the so-called nuMSM (neutrino Minimal Standard Model) of Shaposhnikov and collaborators, which, though, is attained by a different reasoning. If time allows, I will also discuss a novel mechanism for generating such a mass, which goes beyond conventional mechanisms for neutrino masses.
REFERENCES:
[1] Self-interacting dark matter
Nick E. Mavromatos (King's Coll. London), Carlos R. Argüelles (ICRA, Pescara & Buenos Aires, CONICET & Buenos Aires U.), Remo Ruffini, Jorge A. Rueda (ICRA, Pescara & Rome U. & ICRA, Rome & ICRA, Rio de Janeiro). 2016. 28 pp.
Published in Int.J.Mod.Phys. D26 (2016) no.03, 1730007
DOI: 10.1142/S0218271817300075
[2] The role of self-interacting right-handed neutrinos in galactic structure
C.R. Argüelles (Rome U. & ICRA, Pescara & INFN, Rome), N.E. Mavromatos (CERN & King's Coll. London), J.A. Rueda, R. Ruffini (ICRA, Pescara & ICRA, Rome & Rome U.). Jan 31, 2015. 6 pp.
Published in JCAP 1604 (2016) no.04, 038
DOI: 10.1088/1475-7516/2016/04/038
e-Print: arXiv:1502.00136
plenary : Collider searches for DM (ATLAS+CMS)
-->result of negociation with CMS : made by ATLAS
Quantum many-body chaos is described as a practical (theoretical. experimental, and computational) instrument in physics of mesoscopic systems of interacting particles.
Using nuclear, atomic and spin physics applications, it is shown that interactions of constituents
create stationary states of high complexity with respect to the mean-field basis with observable properties smoothly changing along the spectrum. Both local chaotic features and the global evolution along the spectrum are used to understand many-body physics and define
thermodynamic properties of isolated mesoscopic objects (no heat bath). Physical applications,
experimental, theoretical and computational, are discussed. Artificially introduced chaotic elements can be used to explore the landscape of possible states of the system and predict phase transformations.
TBA
Advances in Relativistic Fluid Dynamics,
Observables, and Applications
Fluctuations and correlations
In the next-to minimal supersymmetric standard model (NMSSM) the lightest supersymmetric particle (LSP) is a candidate for the dark matter (DM) in the universe. It is a mixture from the various gauginos and Higgsinos and can be bino-, Higgsino- or singlino-dominated. These different scenarios are discussed in detail and compared with the sensitivity of future direct DM search experiments, where we use an efficient sampling technique of the parameter space.
The results will be compared with the MSSM.
We find that LSPs with a significant amount of Higgsino and bino admixture will have cross sections in reach of future direct DM experiments, so the background from coherent neutrino scattering is not yet limiting the sensitivity.
Both, the spin-dependent (SD) and spin-independent (SI) searches are important, depending on the dominant admixture.
If the predicted relic density is too low, additional dark matter candidates are needed, in which case the LSP direct dark matter searches loose sensitivity of the reduced LSP density. This is taken into account for expected sensitivity.
The most striking result is that the singlino-like LSP has regions of parameter space with cross sections below the "neutrino floor", both for SD and SI interactions. In this region the background from coherent neutrino scattering is expected to be too high, in which case the NMSSM will evade discovery via direct detection experiments. Details on this and connected topics can be found in our papers: arXiv:1703.01255v1, arXiv:1610.07922,arXiv:1602.08707, arXiv:1402.4650, arXiv:1308.1333, arXiv:1207.3185.
Low-energy baryons can be effectively described with regard to most of their properties on the basis of valence-quark configurations. This is particularly the case for the baryonic ground states, e.g. along the relativistic constituent-quark model, lattice quantum chromodynamics, or effective field theories. However, all approaches based on quantum chromodynamics presently struggle with a proper description of baryon resonances. The reasons mainly lie in their strong couplings to a number of hadronic decay channels, which have usually not yet been taken into account explicitly.
In the attempt to construct a relativistic coupled-channels quark model going beyond valence-quark degrees of freedom, we have made a study of explicit pionic effects for the nucleon and Delta. In particular we have investigated in a relativistic coupled-channels framework the influences of the pion channel on the nucleon and Delta masses as well as the pion-nucleon/Delta interaction vertices. Sizeable effects are found already for one-pion dressing. We take this as an indication of the absolute necessity of explicitly including strong-decay channels in a realistic description especially of baryon resonances.
We discuss the cosmological production and the successive
evolution of the electroweak monopole in the standard
model, and estimate the remnant monopole density at present
universe. We confirm that, although the electroweak phase
transition is of the first order, it is very mildly first
order. So, the monopole production arises from the thermal
fluctuations of the Higgs field after the phase transition,
not the vacuum bubble collisions during the phase transition.
Moreover, while the monopoles are produced copiously around
the Ginzburg temperature $T_G\simeq 59.6~{\rm TeV}$, most
of them are annihilated as soon as created. This annihilation
process continues very long, untill the temperature cools
down to about 29.5 MeV. As the result the remnant monopole
density in the present universe becomes very small, of
$10^{-11}$ of the critical density, too small to affect
the standard cosmology and too small comprise a major
component of dark matter. We discuss the physical implications
of our results on the ongoing monopole detection experiments,
in particular on MoEDAL, IceCube, ANTARES, and Auger.
TBA
A classical solution for electromagnetic monopoles induced by gravitational (global) monopoles in the presence of a (four-dimensional) Kalb-Ramond axion field is found. The magnetic charge of such a solution is induced by a non-zero Kalb-Ramond field strength, prevalent in string theory. Bounds from the current run of the LHC experiments are used to constrain the parameters of the model. Because the production mechanism depends on the details of the model and its ultraviolet completion, such bounds, presently, are only indicative.
In this talk the status of the searches for classical magnetic monopoles (MMs) at accelerators, for GUT superheavy monopoles in the penetrating cosmic radiation and for Intermediate Mass MMs at high altitudes is discussed, with the emphasis on most recent results and future perspectives.
The IceCube experiment has instrumented a cubic kilometer of ice with $5160$ photo-multipliers. While mainly developed to detect Cherenkov light, any visible light can be used to detect particles within the ice.
Magnetic monopoles are hypothetical particles predicted by many Beyond the Standard Model theories. They are carriers of a single elementary magnetic charge.
Different light production mechanisms dominate for this class of particle from direct Cherenkov light at highly relativistic velocities ($>0.76\,c$), indirect Cherenkov light at mildly relativistic velocities $\left(\approx 0.5\,c \textrm{ to } 0.76\,c \right)$, luminescence light at low relativistic velocities
$\left(\approx 0.1\,c \textrm{ to } 0.5\,c \right)$, as well as the propose proton decay at non relativistic velocities $\left(< \approx 0.1\,c \right)$.
For each of this speed ranges, searches for magnetic monopoles at the IceCube experiment are either in progress or already set competitive limits on the flux of magnetic monopoles. A summary of these searches will be presented, outlining already existing results as well as methods used by the currently conducted searches.
I will review recent results obtained within the Hamiltonian approach to QCD in Coulomb gauge both at zero and finite temperatures. The temperature is introduced by compactifying a spatial dimension. Results are presented for the chiral and dual quark condensate as well as for the Polyakov loop. The continuum approach is also confronted to recent lattice data.
We present first-principle results for the 1PI correlation functions of two-flavour Landau-gauge QCD in the vacuum. These correlation functions carry the full information about the theory. They are obtained by solving their Functional Renormalisation Group equations in a systematic vertex expansion, aiming at apparent convergence. This work represents an indispensable and pivotal prerequisite for quantitative first-principle studies of the QCD phase diagram and the hadron spectrum within this framework.
In particular, we have computed the gluon, ghost, quark and scalar-pseudoscalar meson propagators, as well as gluon, ghost-gluon, quark-gluon, quark, quark-meson, and meson interactions. Our results stress the crucial importance of the correct semi-perturbative running of the different vertices in order to quantitatively describe the phenomena and scales of confinement and spontaneous chiral symmetry breaking without further phenomenological input. Furthermore, preliminary results for the correlation functions of pure Yang-Mills at finite temperature are presented.
TBA
Comparison of hydrodynamical and transport theoretical calculations for p+A and A+A collisions
Super Heavy Elements - experimental developments
Gottfried Münzenberg
GSI Helmholtzzentrum für Schwerionenforschung mbH, Planckstr. 1, 64291 Darmstadt, Germany
Manipal Centre for Natural Sciences, Manipal University, Manipal 576104, Karnataka, India
G.Muenzenberg@gsi.de
With his theoretical work our mentor Walter Greiner pioneered heavy-and super heavy element research and motivated us as young scientists. As member of the “Kernphysikalische Arbeitsgemeinschaft Hessen, KAH” he actively shaped the profile of GSI. Cold heavy-ion fusion proposed by Yuri Oganessian, theoretically supported by Walter Greiner, paved the way to the super heavy elements. We are happy that still during his lifetime we could prove some of his predictions
Experimental developments paving the way to super heavy elements were the cold fusion of heavy ions to create super heavy nuclei, separation in-flight, and the implantation of the separated nuclei into position sensitive surface-barrier detectors to observe the decay history of individual nuclei. With the discovery of oganesson, Z=118, the heaviest element known today, produced in hot fusion reaction using beams of 48Ca, we have come to the end of this series. New experimental ideas and development are needed and under way.
A primary challenge for SHE research is the search for reactions to pass beyond oganesson and to explore the predicted island of superheavy elements. To measure cross-sections of femtobarns near and beyond Z=118, dedicated SHE factories are under construction. Reaction studies include new target-projectile combinations and transfer reactions. The next-generation of radioactive beam facilities will allow for large-scale studies. To which extent the use of rare-isotope beams can contribute to SHE research is under discussion.
The new SHE facilities include in-flight separators coupled to ion-catchers and multi-reflection time-of-flight mass spectrometers with isobaric mass resolution. These allow the isotopic identification of single atomic nuclei, determining nuclear mass and charge. For the first time superheavy nuclei can be identified directly “still alive” independent from their decay mode. First promising results have already been obtained.
Monpopoles could be created in high-energy collisions of cosmic rays with the atmosphere. Cosmic rays have been bombarding the Earth constantly since the planet formed and if monopoles have been created, then they may be deposited in terrestrial samples of material. I will discuss the feasibility for monopole searches that could use ice core samples from climatology studies to complement sample studies that have been performed previously using other material samples such as rocks or water. This would complement the existing searches for exotic particles at MoEDAL and the LHC general-purpose detectors. The energy reach of monopoles created by cosmic rays is significantly greater than that available at the LHC.
Magnetic monopoles, if they exist, would be produced amply in strong
magnetic fields and high temperatures via the thermal Schwinger process.
Such circumstances arise in heavy ion collisions, for which we have
constructed the cross section for pair production of magnetic monopoles.
We discuss this result, which is largely model independent and show how
it allows the derivation of lower mass bounds for magnetic monopoles. It
also indicates that heavy ion collisions are particularly promising for
experimental searches such as MoEDAL.
.
Experimental investigation of fusion-fission mechanisms for superheavy nuclei
MoEDAL is a pioneering experiment designed to search for highly ionising messengers of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles, that are predicted to existing a plethora of models beyond the Standard Model. It started data taking at the LHC at a centre-of-mass energy of 13 TeV, in 2015. Its ground breaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; and what is the nature of dark matter. MoEDAL purpose is to meet such far-reaching challenges at the frontier of the field. We will present the first results from the MoEDAL detector on Magnetic Monopole production that are the world’s best for Monopoles with multiple magnetic charge. In conclusion, plans to install a new MoEDAL sub-detector designed to search for very long-lived neutral particles as well as mini-charged particles will be very briefly discussed.
The MoEDAL experiment consists of several types of detectors located around the LHCb interaction point at the LHC. Nuclear track detectors are used to look for highly ionizing particles while trapping detectors allow the detection of magnetically charged particles that stop in their volume. Solid state MediPix detectors allow characterization of the background particle flux. The current status of the MoEDAL detector will be discussed along with two planned subdetectors. The first is a scintillator based detector to monitor MoEDAL trapping volumes for the decays of captured very long-lived highly-ionizing electrically charged particles. This subdetector will be placed in an underground laboratory to reduce cosmic ray backgrounds. The second planned subdetector is designed to detect mini-charged particles and will be located approximately 40m from the interaction point of which 30m is shielding rock and concrete.
Etching of the plastic nuclear track detectors from MoEDAL reveals pits that may indicate the passage of highly ionising particles - such as magnetic monopoles. Scanning of the plastic sheets after etching produces image data that is susceptible to automated analysis using modern machine learning techniques. We present some of the challenges involved in this approach and preliminary work we have done in this area.
The large LHC experiments have successfully used distributed (grid, cloud) computing for years. The same infrastructure yields large opportunistic resources for smaller collaborations. In addition, some national grid initiatives make dedicated resources for small collaborations available.
GridPP is a consortium of 19 UK universities, which provides resources and grid specific computing expertise for any experiment with a UK affiliation. I will present an overview of the services available and how to access them. This will include examples of how small collaborations have successfully incorporated distributed computing into their workflows.
I will discuss the approaches taken by these collaborations and how GridPP can facilitate access to distributed computing for your collaboration.
The Bern-Kosower formalism, originally developed around 1990 as a novel way of obtaining on-shell amplitudes in field theory as limits of string amplitudes, has recently shown to be extremely efficient
as a tool for obtaining form factor decompositions of the N gluon vertices. Its main advantages are that
gauge invariant structures can be generated by certain systematic integration-by-parts procedures, making
unnecessary the usual tedious analysis of the non-abelian off-shell Ward identities, and that the scalar,
spinor and gluon loop cases can be treated in a unified way. After discussing the method in general for the
N gluon case, I will show in detail how to rederive the Ball-Chiu decomposition of the three gluon vertex,
and finally present two slightly different decompositions of the four gluon vertex, one generalizing the
Ball Chiu one, the other one closely linked to the QCD effective action.
The worldline formalism is a first quantised approach to quantum field theory, inspired by string theory and based upon the evaluation of point particle path integrals as an alternative to traditional field theory techniques. It represents a reorganisation of the physical information of the theory with the advantage of maintaining manifest gauge invariance and simplifying the calculation of scattering amplitudes.
I will describe recent advances in the worldline approach to non-Abelian field theory, explaining how the coupling to the gauge field can be incorporated into the worldline action by introducing auxiliary "colour" fields. I will show how these colour fields generate Wilson loop interactions and how a novel Chern-Simons term provides a projection onto an irreducible representation of the gauge group. The calculational efficiency of the worldline formalism is preserved by extending a worldline supersymmetry to the include the colour fields. Finally I will sketch a similar approach to pure Yang-Mills theory and some ongoing work on fields in non-commutative space-time with U(N) symmetry.
We review our previous results on SU(2N_F) symmetry
of hadrons upon artificial subtraction of the near-zero
modes of the Dirac operator, which is a symmetry of confinement
in QCD. We show our recent lattice results on spatial correlators
at high temperature that reveal the same SU(2N_F) symmetry which
has far reaching implications for nature and structure of the
strongly interacting matter at high temperatures.
The
fermionic Green’s functions of QCD exhibit an unexpected property of
effective locality, which appears to be exact, involving no
approximation. This property is non-perturbative, resulting from a full
integration of the elementary gluonic degrees of freedom of QCD but can
hardly be thought of in terms of a duality. Recalling and extending
the derivations of effective locality, focus will be put on the way
non-abelian gauge-invariance gets realized in the non-perturbative
regime of QCD. Another very deep aspect of effective locality, regarding
mass scales will be discussed.
We discuss the non-linear effects of the fluctuation in the chiral-restored phase just before the inhomogeneous chiral phase transition. The fluctuations consist of quark-antiquark and quark particle-hole excitations, and included by the random phase approximation within the two-flavor Nambu-Jona-Lasinio model.
The particular roles of thermal and quantum fluctuations can be understood systematically. The fluctuations give rise to the first order phase transition from the chiral-restored phase to the inhomogeneous chiral phase while the phase transition is the second order one within the mean field approximation. The change can be discussed regardless of the type of the inhomogeneous condensate and the effect of the thermal fluctuation is more crucial than the quantum one.
In addition, it is argued that anomalous behavior of the thermodynamic quantities due to the fluctuation should have phenomenological implications for the inhomogeneous chiral transition. Some common features for other phase transitions, such as those from the normal to the inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov state in superconductivity, are also emphasized.
Magnetic monopoles, if they exist, can be produced via various processes in collider experiments. Previous searches for magnetic monopoles at the LHC were carried out for Drell-Yan process. However the cross section of monopole production in the photon-fusion process is dominant compared to the Drell-Yan process. We will show kinematic distributions for spin 0, spin ½ and spin 1 monopoles when they are produced in two photon fusion.
MoEDAL is designed to search for highly ionising emissaries of new physics and extend the discovery horizon of the LHC in a complementary way to ATLAS and CMS. A number of supersymmetric scenarios give rise to highly ionising particles that may be detected, measured and even trapped by the MoEDAL detector. Such scenarios will be reviewed and the sensitivity of MoEDAL will be presented.
Introduction to the Mini-Workshop on Latest Results and New Physics in the Higgs Sector
plenary : BEH overview (ATLAS)
The status of most recent measurements of the Higgs boson properties is presented in this talk.
The studies are based on data recorded by the CMS experiment at 13 TeV.
After the discovery of the Higgs boson, the measurement of its coupling properties are of particular importance. In this talk measurement of the cross sections and couplings of the Higgs boson in ttH production and fermionic decay channels with the ATLAS detector are presented.
We demonstrate the monopole condensation in QCD.
We present the gauge independent and Weyl symmetric
Abelian (Cho-Duan-Ge) decomposition of the SU(3) QCD,
and obtain an infra-red finite and gauge invariant
integral expression of the one-loop effective action.
Integrating it gauge invariantly imposing the color
reflection invariance (``the C-projection'') we show
that the effective potential generates the stable
monopole condensation which generates the mass gap.
We discuss the structure of the deconfining ground state, its particle and wavelike excitations, and how well effective radiative corrections are controlled. In particular, we elucidate the contributions to the pressure of massive 2PI bubble diagrams with dihedral symmetry of arbitrarily high loop order and how these are resummed to exhibit hierarchical suppression compared to one- and two-loop order.
The talk reviews the measurements of the 125 GeV Higgs boson in several final states, performed by the CMS collaboration. The main focus is on results obtained with data from LHC proton-proton collisions at a centre-of-mass energy of 13 TeV.
To be included later
I will review the status of the Higgs field as a probe of the hidden sector. In particular, I will focus on its role as our (possibly) only link to the dark matter and inflaton sectors. I will report on the recent progress in understanding the cosmological implications of metastability of the electroweak vacuum.
A summary of the searches for the rare decays, exotic production and decays of standard model Higgs boson is presented. Foe the rare decays, the results from di-muon, Zgamma, gamma*gamma, J/psi gamma final states will be included. For the searches for exotic production and decays, the invisible and quasi invisible decays, lepton flavour violation (emu, etau, mutau) decays, decays to light scalars, will be reviewed.
Several theories beyond the Standard Model predict enhanced production rates for Higgs Boson pair production. Other theories predict Lepton Flavour Violating decays of the Higgs boson or enhanced decay rates into rare modes like Z-photon, J/Psi-photon, Phi-photon or into pairs of light pseudoscalar bosons "a". In this presentation the latest ATLAS results on searches for these particles will be discussed.
In this report we study the properties of the dense SU(2) QCD. The
lattice simulations are carried out with improved gauge action and
smaller lattice spacing as compared to our previous work.
This allowed us to approach closer to the continuum limit and
reach larger densities without lattice artifacts.
We measured string tension and Polyakov loop as a function
of chemical potential and temperature. At sufficiently large baryon
density and zero temperature we observe confinement/deconfinement
transition which manifests itself as a vanishing of string tension and
rising of Polyakov loop.
We plan to discuss appearance of effective gluon masses in lattice experiments in the Landau gauge gluodynamics framework. We consider both gluon propagator in momentum space and zero-momentum correlator in coordinate space (the latter under various boundary conditions) and observe characteristic "massive" behaviour of correlators considered.
Professor Walter Greiner, our friend and teacher, passed away in the age of eighty. During his lifetime, the search for elements beyond uranium started and elements up to the so far heaviest one with atomic number 118 were discovered. In this talk I will present a short history from early searches for ‘trans-uraniums’ up to the production and safe identification of shell-stabilized ‘Super-Heavy Nuclei (SHN)’. The nuclear shell model reveals that these nuclei should be located in a region with closed shells for the protons at Z = 114, 120 or 126 and for the neutrons at N = 184. The outstanding aim of experimental investigations is the exploration of this region of spherical SHN. Systematic studies of heavy ion reactions for the synthesis of SHN revealed production cross-sections which reached values down to one picobarn and even below for the heaviest species. The systematics of measured cross-sections can be understood only on the basis of relatively high fission barriers as predicted for nuclei in and around the island of SHN. A key role in answering some of the open questions plays the synthesis of isotopes of element 120. Attempts aiming for synthesizing this element at the velocity filter SHIP will be reported.
We study the structure of vorticity and hydrodynamic helicity fields in peripheral heavy ion collisions using the kinetic Quark-Gluon String and Hadron-String Dynamics models. We observe the formation of specific toroidal structures of vorticity field (vortex sheets). Their existence is mirrored in the polarization of hyperons of the percent order. Its rapid decrease with energy was predicted and recently confirmed by STAR collaboration. The energy dependence is sensitive to the temperature dependent term derived and discussed in various theoretical approaches. The antihyperon polarization is of the same sign and larger magnitude. The crucial role of strange vector mesons is also discussed.
The Higgs trilinear coupling is still a missing piece in the Standard Model puzzle. Although its theoretical value can be extracted from its relation to the mass of the Higgs and the Fermi constant, its measurement through the double Higgs production is particularly challenging. We explore the possibility of probing an anomalous trilinear coupling indirectly, through the production and decay of a single Higgs. Indeed, although these processes do not depend on this coupling at tree level, they are sensitive to the Higgs self-coupling at NLO. This gives us the opportunity to derive the constraints on the trilinear coupling from various observables, like the signal strength of the different channels or the cross-section of the associate Higgs production with top quarks.
Summarise the status of the searches for new physics in HH final state at CMS and projections for CMS
Resonance production in Pb-Pb collisions measured with the ALICE detector at the LHC
V. Riabov for the ALICE Collaboration
Hadronic resonances are very useful in exploring various aspects of heavy-ion collisions. Due to their short lifetimes, yields of resonances measured via hadronic decay channels can be affected by particle rescattering and regeneration in the hadronic gas phase. The momentum dependence of rescattering and regeneration cross sections may also modify the observed momentum distributions of the reconstructed resonances. Resonances as hadrons with different masses and quark composition also contribute to the systematic study of in-medium parton energy loss at high transverse momentum and help to distinguish among different mechanisms responsible for particle production at intermediate momentum.
In this talk we present the most recent ALICE results on $\rho(770)^{0}$, $K*(892)^{0}$, $\phi(1020)$, $\Sigma(1385)^{\pm}$$\Lambda(1520)$ and $\Xi(1530)^{0}$ production in pp, p-Pb and Pb-Pb collisions at various collision energies including results from the latest Pb-Pb run at $\sqrt{s_{NN}}$ = 5.02 TeV. The comprehensive set of resonance measurements is used to study strangeness production, the role of re-scattering and regeneration in the hadronic phase as well as particle production at intermediate and high transverse momentum. Production spectra, integrated yields, mean transverse momenta and particle ratios are presented, discussed and compared to model predictions and lower energy measurements.
Heavy quarks (charm and beauty) are a powerful tool to study the properties of the Quark-Gluon Plasma (QGP), the hot and dense medium formed in high-energy heavy-ion collisions. Due to their large masses, heavy quarks are produced in hard partonic scattering processes in the initial stages of the collision. Therefore, they experience the whole system evolution interacting with the medium constituents. The measurement of heavy-flavour production can give us different information depending on the type of collision. In p-Pb collisions, it makes it possible to study cold nuclear matter effects, such as shadowing, $k_{\rm T}$ broadening and initial-state energy loss, as well as possible geometrical and collective effects in high-multiplicity events. In Pb-Pb collisions, it allows us to test parton energy-loss models and to investigate the participation of heavy quarks in the collective expansion of the system.
In ALICE, open charm production is measured through the full reconstruction of D-meson hadronic decays at mid-rapidity.
In this talk, the ALICE results on the production of prompt D mesons in p-Pb and Pb-Pb collisions will be presented, focusing on the recent results from LHC Run II data.
The main physical observables measured are: the nuclear modification factor ($R_{\rm AA}$), which compares the D-meson yields in p-Pb (Pb-Pb) collisions to the binary scaled D-meson yields in pp collisions, and the elliptic flow ($v_2$), the second Fourier coefficient of the D-meson azimuthal distribution. We will report the D-meson cross section and nuclear modification factor in p-Pb collisions as a function of the event multiplicity. In addition, the $R_{\rm AA}$ and $v_2$ in different Pb-Pb collision centralities will be discussed. The results will be also compared with theoretical predictions.
Photon and electron identifications are a crucial input to many ATLAS physics analysis.
The identification of prompt photons and the rejection of background coming mostly from photons from hadron decays relies on the high granularity of the ATLAS calorimeter.
The electron identification used in ATLAS for run 2 is based on a likelihood discrimination to separate
isolated electron candidates from candidates originating from photon conversions, hadron misidentification
and heavy flavor decays. In addition, isolation variables are used as further handles to separate
signal and background. Several methods are used to measure with data the efficiency of the photon identification requirements, to cover a broad energy spectrum. At low energy, photons from radiative Z decays are used. In the medium energy range, similarities between electrons and photon showers are exploited using Z->ee decays. At high energy, inclusive photon samples are used. The measurement of the efficiencies of the electron identification and isolation
cuts are performed with the data using tag and probe techniques with large statistics sample of Z->ee
and J/psi->ee decays. These measurements performed with pp collisions data at sqrt(s)=13 TeV in 2016 (2015)
corresponding to an integrated luminosity of 33.9 (3.1)fb-1 of sqrt(s)=13 TeV pp are presented.
A search for new physics in events with jets, b-tagged jets, missing transverse momentum, and 0-leptons, corresponding to an integrated luminosity of 35.9 fb−1 collected by the CMS experiment at √s = 13 TeV, is presented. No significant excess of events above the standard model background expectation is observed. Results are interpreted in terms of a number of simplified supersymmetry models, corresponding to di-gluino production, as well as 1st and 3rd generation di-squark production, with a variety of gluino and squark decay modes. For a massless lightest supersymmetric particle, lower limits on the gluino (squark) mass are established in the range 1.80-1.95 TeV (1.00-1.05 TeV), depending on the model considered.
In this talk, we extend the Faddeev-Popov construction of the familiar linear covariant gauge. We take into account the Gribov gauge fixing ambiguity. We pay attention to the BRST invariance of the construction, its renormalizability and we discuss the Nielsen identities that restrict the pole structure of the non-perturbative propagators.
We also make a bridge to the lattice version of the linear covariant gauge, in particular to suitably define the ghost propagator.
Finally, we also show, for the 1st time to our knowledge, how to derive the non-Abelian Landau-Khalatnikov-Fradkin transformations, which implement a gauge variation at the level of quantum correlation functions. We verify the well-established Abelian limit case and specify, also for the non-Abelian case, the special role of the Landau gauge.
It took more than 40 years until Lattice QCD tools have become evolved far
enough to address excited hadrons in a reliable way. Still, we are confined to
the low lying resonances with a few coupled two-hadron channels, mostly in the
meson-meson sector. Phase shifts at a few energy values for simple system have
been determined in this first principles approach. Meson-nucleon results are
scarce. Comparison of lattice results with model calculations are helpful. I
will survey methods and highlights in the light and heavy quarks sector.
A novel equation of state with the surface tension induced by particles interaction was generalized to describe properties of the neutron stars. Interaction between particles accounted via hard-core repulsion taken into account by the proper volumes of particles and phenomenological attraction term. Recently, this model was successfully applied to the description of the properties of nuclear and hadron matter created in collisions of nucleons. New model is free of causality problems and fully thermodynamically consistent that enable us to use it to the investigation of the strongly interacting matter phase diagram properties in wide range of temperatures and baryon densities, including neutron stars. We calculated the mass-radius relations for a compact star using the Tolmann-Oppenheimer-Volkov equation for two sets of parameters which satisfy the existing constraints. The found values of the model parameters are in good correspondence with the nuclear-nuclear collision results.
In this talk I will touch upon several features of modern ab initio low-energy nuclear theory. I will start by discussing what "ab initio" means in this context. Specifically, I will spend some time going over nucleon-nucleon and three-nucleon interactions and their connections with the underlying theory of Quantum Chromodynamics. I will then show how these interactions are combined with many-body techniques to describe infinite nucleonic matter, which is of astrophysical relevance. In addition to results on the equation-of-state of homogeneous matter [1,2,3], I will also discuss recent work on the static response of neutron matter, as well as its consequences for neutron stars [4,5].
[1] A. Gezerlis et al, Phys. Rev. Lett. 111, 032501 (2013).
[2] A. Gezerlis et al, Phys. Rev. C 90, 054323 (2014).
[3] I. Tews, S. Gandolfi, A. Gezerlis, and A. Schwenk, Phys. Rev. C 93, 024305 (2016).
[4] M. Buraczynski and A. Gezerlis, Phys. Rev. Lett. 116, 152501 (2016).
[5] M. Buraczynski and A. Gezerlis, Phys. Rev. C 95, 044309 (2017).
TBA
Highly charged ions (HCI) combine extremely strong electromagnetic fields and a simple electronic structure, which makes them ideal testing grounds for fundamental theories such as quantum mechanics, relativity and quantum electrodynamics (QED) in the domain of strongest electromagnetic fields available for experimental investigation. In the heaviest one- and few-electron ions, such as hydrogen-like uranium, the field strength exposed on the electron in the ground-state is already very close to the Schwinger limit. Therefore, the structure (and also the dynamics) of highly-charged ions is significantly influenced by the effects of the quantum vacuum.
The new international accelerator Facility for Antiproton and Ion Research (FAIR) which is currently under construction in Darmstadt, offers a wide range of exciting new opportunities in the field of atomic physics and related fields. These include (among others); cooled and stored heavy-ion beams of excellent quality and intensity, with a very broad energy range; from relativistic down to virtually at rest.
In this presentation, an overview of the program of the Stored Particle Atomic Research Collaboration (SPARC) at the FAIR facility will be given. Particular emphasis will be on precision experiments with highly-charged heavy ions devoted to stringent tests of Quantum Electrodynamics in extreme electromagnetic fields as well as to the experimental program aimed to study low-energy (near-)symmetric ion-atom/ion collisions in storage rings at GSI and FAIR. One of the main (long-term) goals here is to gain better insight into the details of heavy quasi-molecular systems formed in such encounters and thereby access the physics of critical electromagnetic fields.
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Several theories beyond the Standard Model, like the EWS or 2HDM models, predict the existence of high mass neutral or charged Higgs particles. In this presentation the latest ATLAS results on searches for these particles will be discussed.
A reanalysis of LEP data has shown a slight excess in a channel characterised by two muons and bottom quarks. Triggered by this fluctuations, I will discuss phenomenological scenarios of new physics which can generate such signature and discuss their compatibility with data from LHC currently under scrutiny.
We present a measurement of the $Z \rightarrow b\bar{b}$ production cross section in $p\bar{p}$ collisions at $\sqrt s = 1.96 TeV$. We use a data set of 5.46 $fb^{-1}$ collected by the CDF experiment at the Tevatron collider during Run II using a dedicated trigger path which required a displaced vertex compatible with a b-hadron decay. A data-driven procedure is applied to estimate the dijet mass spectrum of the non-resonant multijet background. Using a similar strategy we set one of the most stringent upper limits on the production of a Higgs-like particle in association with b quarks. We also set a limit on the inclusive SM $H \rightarrow b\bar{b}$ .
A search for anomalous quartic photon coupling with forward proton tagging is presented. The motivation for this coupling stems from theories of new phenomena (Composite Higgs, Kaluza-Klein, Warped Extra Dimensions). Forward proton tagging in CMS-TOTEM and Atlas Forward Physics spectrometers allows us to search for anomalous couplings with an unprecedented sensitivity. By imposing conservation of four-momenta on the system, we are able to probe a background free selection in a model independent way. This independence allows us to consider applications such as generic contributions from charged and neutral particles as well as dark matter searches.
The ALICE experiment has measured the production of identified light-flavour hadrons in p-Pb and Pb-Pb collisions at 5.02 TeV in a wide range of transverse momentum (pT ). The newest ALICE results on pion, kaon and proton transverse momentum spectra, yield ratios and nuclear modification factors will be presented and discussed in comparison to lower energy results and hydrodynamical models. In particular, the production of identified hadrons in most central Pb-Pb collisions relative to pp collisions is found to be strongly suppressed at high transverse momenta (pT > 8 GeV/c) whereas in p-Pb collisions the nuclear modification factors are consistent with unity. This indicates that the strong suppression of high- pT hadrons measured in central Pb-Pb collisions is not due to an initial state effect but instead to the energy loss of partons traversing a hot and dense QCD medium.
The measurement of the mixing-induced CP-violating phase phi_s in the Bs-Bsbar system is one of the key goals of the LHCb experiment. It has been measured at LHCb exploiting the Run I data set and using several decay channels. In particular, the most recent Run I results have been obtained analyzing Bs0->J/psi(->mu+mu-) K+K- candidates in the mass region above the phi(1020) resonance and Bs0 -> Jpsi(->e+e-) phi candidates. However, the precision of phi_s is still limited by the statistics. In this conference, we will present recent results obtained analyzing the Run-II data collected during 2015-2016. Namely, we will present measurements obtained analyzing the golden channel, Bs0->J/psi K+K- in phi(1020) region, and Bs0->J/psi pi+pi-, both with J/psi->mu+mu-.
We consider a non-ideal hot pion gas with the dynamically fixed number of particles in the model with the $\lambda\phi^4$ interaction. The effective Lagrangian for the description of such a system is obtained after dropping the terms responsible for the change of the total particle number. Reactions $\pi^+\pi^-\leftrightarrow\pi^0\pi^0$, which determine the isospin balance of the medium, are permitted. Within the self-consistent Hartree approximation we compute the effective pion mass, thermodynamic characteristics of the system and the variance of the particle number at temperatures above the critical point of the induced Bose-Einstein condensation when the pion chemical potential reaches the value of the effective pion mass. We analyze conditions for the condensate formation in the process of thermalization of an initially non-equilibrium pion gas. The normalized variance of the particle number increases with a temperature decrease but remains finite in the critical point of the Bose-Einstein condensation. This is due to the non-perturbative account of the interaction and is in contrast to the ideal-gas case. In the kinetic regime of the condensate formation the variance is shown to stay finite also.
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results on inclusive searches for supersymmetric squarks and gluinos, including third generation squarks produced in the decay of gluinos, and considering both R-parity conserving and R-Parity violating SUSY scenarios. The searches involve final states containing jets, missing transverse momentum with and without light leptons, taus or photons, as well as long-lived particle signatures.
Many supersymmetry models feature gauginos and also sleptons with masses less than a few hundred GeV. These can give rise to direct pair production rates at the LHC that can be observed in the data sample recorded by the ATLAS detector. The talk presents results from searches for gaugino and slepton pair production in final states with leptons or long-lived particles, using the data collected during the LHC Run 2.
Particles containing heavy quarks are produced in LHC pp collisions at 7, 8, and 13 TeV and constitute an excellent laboratory to test the Standard Model and probe for New Physics effects. Recent results by the CMS Collaboration on heavy flavor production and properties are reported.
The Belle II experiment at the asymmetric $e^+e^−$ SuperKEKB collider is a major upgrade of the Belle experiment, which ran at the KEKB collider at the KEK laboratory in Japan. The design luminosity of SuperKEKB is $8×10^{35}$ cm$^{−2}$ s$^{−1}$, which is about 40 times higher than that of KEKB. The expected integrated luminosity of Belle II is 50 ab$^{−1}$ in five years of running. The experiment will focus on searches for new physics beyond the Standard Model via high precision measurements of heavy flavor decays, and searches for rare signals. To reach these goals, the accelerator, detector, electronics, software, and computing systems are all being substantially upgraded. In this talk we present the status of the accelerator and Belle II detector upgrades, as well as the expected sensitivity to new physics of the Belle II data set.
We investigate the predictions of Nambu-Goto (NG) and Polyakov-Kleinert (PK) effective string actions for the Casimir energy and the width of the quantum delocalization of the string at two loop order in 4-dim pure SU(3) Yang-Mills lattice gauge theory. Intermediate and large color source separation distance, before the string breaks in full QCD, at two temperature scales are considered near the deconfinement point.
At a temperature closer to the critical point $T /T_c = 0.9$, we found that the next to leading-order (NLO) contributions from the expansion of the NG string to improve the match to lattice data in the intermediate distance scales for both the quark-antiquark potential and broadening of the color tube compared to the free string approximation. Nevertheless, the Nambu-Goto string action in the next-to-leading order approximation does not provide a precise match with the numerical data for both the quark-antiquark potential and broadening profile.
We conjecture possible stiffness of the QCD string through studying the effects of extrinsic curvature term in Polyakov-Kleinert action. The consequences of adding a smoothing term proportional to the extrinsic curvature to the Nambu-Goto string action, as suggested by Polyakov, are investigated. The mean square width of the flux tube of the smooth open-string is derived considering Dirichelet boundary condition. We find that the theoretical predictions derived based on this smooth string formalism return a good fitting behavior for the lattice Mont-Carlo data at both long and intermediate quark separations regions.
In this talk we will discuss the $SU(3)$--gluodynamics shear viscosity temperature dependence on the lattice. We measured the correlation functions of the energy-momentum tensor in the range of temperatures $T/T_c \in [0.9, 1.5]$ and extracted shear viscosity using two approaches. The first one was to fit the lattice data with a physically motivated ansatz for the spectral function with unknown parameters and then determine the shear viscosity. The second approach was to apply the Backus-Gilbert method allowing to extract the shear viscosity from the lattice data nonparametrically. The results obtained within both approaches agree with each other. Our results allow us to conclude that within the range $T/T_c \in [0.9, 1.5]$ the $SU(3)$--gluodynamics reveals the properties of a strongly interacting system, which cannot be described perturbatively, and has the ratio η/s close to the value $1 / 4 \pi$ of the $N = 4$ Supersymmetric Yang-Mills theory.
In nuclear physics, superheavy and hypernuclei are two of the most important fields of research. The prediction of islands of superheavy elements (Z = 114, N = 184, 196 and Z = 164, N = 318) in late sixties by the Frankfurt school played a key role in extending the periodic table of elements up to atomic number 118. Similarly, the demonstration that nuclear matter can be compressed 510 times of its original volume by nuclear shock waves, produced during heavy ion collision, led to the production of single- and double-lambda hypernuclei, as well as anti-matter nuclei. Recent observation of antihypertriton—comprising an antiproton, an antineutron, and an antilambda hyperon, by the STAR collaboration has now made it possible to envision a 3-dimensional nuclear chart of hypernuclei. My own interest in superheavy and hypernuclei was shaped from my first meeting with Walter Greiner at the International Conference on Atomic and Nuclear clusters held at Santorini, Greece in 1993. I will present a brief summary of these exciting developments, including some of our own work. Professor Greiner’s vision, enthusiasm, and encouragement touched many lives and I was one of those privileged ones.
α decay is one of the main decay modes of Super-heavy nuclei (SHN) and highly neutron deficient medium-mass nuclei, collectively termed `exotic´ nuclei. In the synthesis of such nuclei and the radiochemical characterization of their longer-lived decay products, the identification is aided by the theoretical predictions of α decay half-lives (T1/2) and decay energies. We examine the ability of 3 phenomenological alpha decay formulae, the Generalised Liquid Drop Model (GLDM), the Sobiczewski-Parkhomenko and the Viola-Seaborg formulae, to predict the α partial T1/2 of 100 exotic nuclei by the statistical quantification of their accuracy and precision. These quantities were derived using a method based on standard experimental benchmarking wherein the α spectroscopic data of 302 well-established alpha decaying nuclei (calibration data set) were used. Experimental masses as well as Finite Range Droplet Model masses were used to compute Qα. Improved coefficients for the three formulae were derived resulting in modified formulae. A simple linear optimization allowed adjustment of the modified formulae for the insufficient statistics of the odd-even and odd-odd decays of the calibration data set, without changing the modified formulae. Relatively better figures of merit for the odd-odd and the SHN were obtained using the modified GLDM formula.
Ultrarelativistic nuclear collisions provide unique possibility to
study the matter at extreme conditions not available in any other
laboratory settings. These include highest temperature and energy
density, strongest electro-magnetic fields, lowest viscosity over
entropy density (ideal liquid) and, what is the main theme of this
presentation, the highest vorticity, originating in the large angular
momentum of the system. I will present the recent developments in
understanding of the role of vorticity in high energy nuclear
collision dynamics, as well as latest experimental measurements of the
global polarizations - the particle spin alignment with the system
orbital momentum. The relation of the global polarization effect to
Barnett and Einstein-de Haas effects, as well as to chiral anomalous
effects, both in nuclear collisions and condensed matter, will be also
briefly discussed.
Visit to the Monastery and Museum Gonia and talk in the Veranda of the Museum
plenary talk : ATLAS overview highlight talk
LHCb overview
The absence of any direct signals of new particles or force carriers at the LHC forces us to contemplate the real possibility of what was called the nightmare scenario a decade ago : the LHC has found the Higgs, but the physics which lies beyond the Standard Model (BSM) also lies beyond its energy reach. A growing number of flavour physics anomalies, however, may not only be giving us a glimpse of BSM particles, but can also help us to understand their properties long before any direct detection is possible. In this talk I will review the current flavour physics anomalies and their possible interpretations, before describing how the upgrades of the LHCb detector will drive a precise understanding of these anomalies and any BSM physics which may be causing them. In particular, I will discuss the physics case for the recently proposed Phase II upgrade of the LHCb detector, which aims to collect 300fb-1 of data at an instantaneous luminosity of 2e34cm-2s-1 from 2031 onwards. Key to this physics case will be extending the full real-time analysis of the collected data, pioneered by LHCb since 2015, to the 1000 times greater data rate of the Phase II upgrade, and I will discuss this and the other technical challenges which will have to be overcome in order to fully understand what flavour is telling us about possible BSM physics and where it may be found.
The High Luminosity LHC (HL-LHC) targets a rich physics programme with a total integrated luminosity of 3000 fb-1. The collider will produce an unprecedented number of Higgs bosons, which will greatly improve the precision of measuring the properties of the state at 125 GeV. Also the reach of searches for additional Higgs bosons is considerably extended. This presentation will review projections from the ATLAS and CMS experiments for Higgs physics at the HL-LHC.
Baryons are the extended family of the proton and the neutron, containing three quarks out of possible five progressively heavier "flavors" - up (u), down (d), strange (s), charm (c) and bottom (b).
I will describe the prediction and the very recent experimental discovery of the first doubly-heavy baryon Xi_cc^{++}, with quark content (ccu) and mass
3621.40 +- 0.72 +- 0.27 +- 0.14 MeV, very close to our theoretical prediction 3627 +- 12 MeV.
We study a "classical" bouncing scenario in beyond Horndeski theory. We give an example of spatially flat bouncing solution that is non-singular and stable throughout the whole evolution. The model is arranged in such a way that the scalar field driving the cosmological evolution initially behaves like full-fledged beyond Horndeski, whereas at late times it becomes a massless scalar field minimally coupled to gravity.
Based on arXiv:1705.06626 [hep-th]
Following a period of inflation one must reheat the Universe, and a particularly efficient way to do this is through preheating, where the homogeneous inflaton condensate produces particles due to a resonance.
The break-up of the inflaton condensate can lead to long-lived localized lumps of oscillating condensate, known as oscillons, and we shall show that these lumps are able to produce particles in a similar manner to preheating physics, even producing fermions that are heavier than the condensate field itself.
TBA
The origin of ultra-high energy cosmic rays (UHECRs) has been a long-standing mystery. The Telescope Array (TA) is the largest experiment in the northern hemisphere observing UHECR in Utah, USA. It aims to reveal the origin of UHECR by studying the energy spectrum, mass composition and anisotropy of cosmic rays. TA is a hybrid detector comprised of three air fluorescence stations which measure the fluorescence light induced from cosmic ray extensive air showers, and 507 surface scintillator counters which sample charged particles from air showers on the ground. We present the cosmic ray spectrum observed with the TA experiment. We also discuss our results from measurement of the mass composition. In addition, we present the results from the analysis of anisotropy, including the excess of observed events in a region of the northern sky at the highest energy. Finally, we introduce the TAx4 experiment which quadruples TA, and the TA low energy extension (TALE) experiment.
A nonlinear interferometer, generally, is a sequence of two nonlinear effects occurring coherently. We investigate the properties of such an interferometer consisting of two unseeded high-gain degenerate optical parametric amplifiers (DOPAs). This configuration is known in the literature as an SU(1,1) interferometer and it enables achieving the Heisenberg limit in phase sensitivity. Moreover, by making the two DOPAs unbalanced, the parametric gain of the second one considerably exceeding the one of the first one, one can overcome the detection losses [1].
In our experiment, we demonstrate a phase sensitivity overcoming the shot noise limit by more than 2dB, with the number of photons in the interferometer being between 1 and 10. We show that the phase sensitivity is considerably improved by increasing the parametric gain of the second DOPA.
The observed tolerance to detection losses will be very important for phase measurements, including the ones related to gravitational-wave detection, in ‘difficult’ spectral ranges where detection is inefficient.
[1] M. Manceau, F. Khalili, and M. Chekhova, New Journal of Physics 19, 013014 (2017).
Ultra-precise measurements of various parameters such as the mass of nano-particles, magnetic fields or gravity can be attained by probing the phononic modes of a micro-mechanical oscillator with light. The sensitivity of such measurements is in part governed by the noise of the phononic mode as well as the noise of the probing light mode, so by decreasing the noise of the probe beam an enhanced sensitivity can be expected. We demonstrate this effect by using squeezed states of light where the quantum uncertainty of the relevant quadrature is reduced below the shot noise level. Using this squeezing-enhanced sensitivity effect, we demonstrate 1) improved feedback cooling of a phononic mode in a microtoroidal cavity and 2) improved sensing of a magnetic field using the coupling to a microtoroidal phononic mode via a magnetorestrictive material. We present our recent experimental results and discuss future directions.
The talk will present an overview of recent theoretical and experimental activities in highly nonlinear quantum optics and optomechanics with continuous variables and a progress in current merging of these two fields. First, we will focus on a generation of instable strong cubic quantum nonlinearities for optical, atomic and optomechanical systems and diagnostics of non-equilibrium and nonclassical states produced by that nonlinearity. Second, we will concentrate on thermally induced nonlinear effects producing nonclassical states of light and motion.
Quantum optics allows implementing cryptographic protocols that are verifiably immune against any conceivable attack. Standard telecommunication components allow for an efficient implementation of quantum communication using continuous-variables (CV) of light. At MPL, we routinely implement CV quantum communication based on phase-shift keying of coherent states in combination with homodyne detection [1,2].
Existing fiber infrastructure is not suitable for long-haul links between metropolitan networks since classical telecom repeaters cannot relay quantum states. A space borne Laser Communication Terminal (LCT), however, would be capable to relay quantum key distribution (QKD) between a large number of hubs on ground. To this end, we demonstrated quantum-limited measurements of signals from the Alphasat satellite in geostationary Earth orbit (GEO) [3]. Our results underpin the feasibility of satellite quantum communication based on existing technology.
On the fundamental research side, the large gravitational potential difference between GEO and ground offers an ideal testbed to investigate gravitational effects on quantum states.
Our measurements from the Alphasat satellite showed that atmospheric noise can be overcome and that merely the huge diffraction losses pose challenges for the detection of quantum properties such as quantum squeezing.
For homodyne detectors in classical telecommunication, the precise measurement value of the continuous quadrature observable is of minor significance. The signals in BPSK encoding, for instance, are discriminated based on the sign of the measurement outcome, such that the signals are often projected onto their sign bit thereby precluding the access to the continuous quadrature spectrum. We investigate the implications of this extremal discretization with regard to the detection of quantum squeezing and find that it can still be witnessed efficiently [4].
[1] B. Heim et al., arXiv:1402.6290v2[quant-ph]
“Atmospheric continuous-variable quantum communication”
New Journal of Physics 16, 113018 (2014)
[2] C. Peuntinger et al., arXiv:1406.1321v1[quant-ph]
“Distribution of Squeezed States Through an Atmospheric Channel”
Phys. Rev. Lett. 113, 060502 (2014)
[3] K. Günthner et al., arXiv:1608.03511v2[quant-ph] (2016)
“Quantum-limited measurements of optical signals from a geostationary satellite”
(accepted in Optica)
[4] C. R. Müller et al.
„ Witnessing Quantum Squeezing via Binary Homodyne Detection“
(in preparation)
ALICE Overview
The STAR experiment has produced convincing evidence that strongly
interacting partonic matter, Quark Gluon Plasma (QGP), is created in the
central collisions of heavy ions. Among the probes used experimentally
to study the QGP properties, the hard probes: jets and heavy flavor
quarks are unique since they are dominantly produced at the early stages
of the collision and subsequently experience the entire evolution of the
system. With its large and uniform acceptance STAR is well-equipped to
study jets in the QGP matter. Moreover during recent years including
the Heavy Flavor Tracker and the Muon Telescope Detector, STAR has
launched a comprehensive heavy-flavor program which enables unique high
precision measurements of charm and bottom quark and quarkonia
properties. In this talk, recent STAR results on jets, open heavy
flavor and quarkonia measurements will be discussed.
During its second run of operation (Run 2) which started in 2015, the LHC will deliver a peak instantaneous luminosity that may reach 2 * 10^34 cm^-2 s^-1 with an average pile-up of about 55, far larger than the design value. Under these conditions, the online event selection is a very challenging task. In CMS, it is realized by a two-level trigger system: the Level-1 (L1) Trigger, implemented in custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the offline reconstruction software running on a computer farm.
In order to face this challenge, the L1 trigger has been through a major upgrade compared to Run 1, whereby all electronic boards of the system have been replaced, allowing more sophisticated algorithms to be run online. Its last stage, the global trigger, is now able to perform complex selections and to compute high-level quantities, like invariant masses. Likewise, the algorithms that run in the HLT go through big improvements; in particular, new approaches for the online track reconstruction lead to a drastic reduction of the computing time, and to much improved performances. This presentation will describe the performance of the upgraded trigger system in Run 2.
TBA
The description of the structure of nuclei in the framework of effective mean-field models are remarkably successful over almost the entire periodic table. Relativistic and non-relativistic versions of this approach enable an effective description of the nuclear many-body problem as an energy density functional. Such theories are used with great success in all quantum mechanical many-body systems. In Coulombic systems, density functional theory is exact and can be derived from the bare Coulomb force without additional phenomenological parameters. In nuclear physics with spin and isospin degrees of freedom, the situation is much more complicated due to the strong nucleon-nucleon and three-body forces. At present, all attempts to derive these functionals directly from the bare forces do not reach the required accuracy. In recent years, however, there have been several attempts to derive semi-microscopic functionals. They start with microscopic Brueckner-Hartree-Fock calculations in nuclear matter. These results are then mapped on a Walecka model to adjust in this way basic properties of the covariant density functionals. Only very few additional, phenomenological parameters are necessary to for a fine-tuning and in this way universal covariant density functionals have been derived which provide an excellent description of ground states and excited states all over the periodic table with a high predictive power.
These semi-microscopic functionals suffer from the fact, that there form is not directly derived from ab initio calculations, only there parameters are adjusted. Therefore, recently, Relativistic Brueckner-Hartree-Fock
theory in finite nuclei has been used to derive the self-consistent mean field and the ground state properties of spherical doubly closed shell nuclei. Starting from a realistic bare nucleon-nucleon (NN) force adjusted to nuclear scattering data, the relativistic G-matrix is obtained as an effective interaction by solving the Bethe-Goldstone equation in a self-consistent basis. This G-matrix is inserted in a relativistic Hartree-Fock code for finite nuclei and in each step of the iteration a new G-matrix is calculated by solving the Bethe-Goldstone equation for the Pauli-operator derived from the corresponding Fermi surface in the finite system. The self-consistent solution of this iteration process allows to calculate ground state properties of finite nuclei without any adjustable parameters. No three-body forces are used. First results are shown for the doubly magic nuclei $^{4}$He, $^{16}$O, and $^{48}$Ca. Their ground state properties, such as binding energies, charge radii, or spin-orbit splittings are largely improved as compared with the results obtained from non-relativistic Brueckner-Hartree-Fock theory. It is discussed that this theory provides a method to study also the ground state properties of heavy nuclei in \textit{ab initio} calculations.
$^{*}$ Work supported by the DFG (Germany) cluster of excellence "Origin and
Structure of the Universe" (www.universe-cluster.de)
Statistical methods have been the focus of increasing attention at LHC experiments, for instance in the context of Higgs searches and measurements carried out by the ATLAS and CMS experiments. This presentation will review the various techniques used by the ATLAS experiment to estimate confidence interval and set upper limits on physical quantities, and to compute discovery p-values and significances to quantify deviations with respect to the standard model expectation.
Observations of short gamma-ray bursts indicate ongoing energy injection following the prompt emission, with the most likely candidate
being the birth of a rapidly rotating, highly magnetised neutron star.
In this talk we discuss how X-ray observations of the burst remnant
can constrain properties of the nascent neutron star (such as the magnetic field-induced ellipticity and the saturation amplitude of various oscillation modes) and derive strict upper limits on the gravitational wave emission from these objects.
The present analysis is motivated by the fact that, although the local Lorentz invariance is one of the cornerstones of modern physics, cosmologically a preferred system of reference does exist.
Modern cosmological models are based on the assumption that there exists a typical (privileged) Lorentz frame, in which the universe appear isotropic to "typical" freely falling observers.
The discovery of the cosmic microwave background provided a stronger support to that assumption
(it is tacitly assumed that the privileged frame, in which the universe appears isotropic, coincides with the CMB frame).
The view, that there exists a preferred frame of reference, seems to unambiguously lead to the abolishment of the basic principles of the special relativity theory: the principle of relativity
and the principle of universality of the speed of light.
Correspondingly, the modern
versions of experimental tests of special relativity and the "test theories" of special relativity
reject those principles and presume that a preferred inertial reference frame, identified with the CMB frame, is the only frame in which
the two-way speed of light (the average speed from source to observer and back) is isotropic
while it is anisotropic in relatively moving frames.
In the present study, the existence of a preferred frame is incorporated into the framework of the special relativity, based on the relativity principle and universality of the (two-way) speed of light, at the expense of the freedom in assigning the one-way speeds of light that exists in special relativity.
In the framework developed, a degree of anisotropy of the one-way speed
acquires meaning of a characteristic of the really existing anisotropy caused by motion of an inertial frame relative to the preferred frame.
The anisotropic special relativity kinematics
is developed based on the first principles: (1) Space-time transformations between inertial frames leave the equation of anisotropic light propagation
invariant and (2) A set of the transformations possesses a group structure. The Lie group theory apparatus is applied as in [1] to define groups of transformations.
The corresponding extension to general relativity, like the standard general relativity, is based on the existence of locally inertial frames and the equivalence principle. Despite the fact that, in the special relativity with a preferred frame developed as described above, the interval is not invariant but conformally modified under the transformations between inertial frames, the complete apparatus of general relativity can be applied based on the existence of an invariant combination which, upon a change of the time and space variables, takes the form of the Minkowski interval. However, to calculate physical effects, an inverse change of variables to the 'physical' time and space is needed. Among the applications of the relativity with a preferred frame, is a possible resolution of the so-named 'acceleration problem' which appeared after the discovery that the present expansion of the universe is accelerated, made using the luminosity distance versus redshift relation of type Ia supernovae. It is interpreted as that the time evolution of the expansion rate cannot be described by a matter-dominated Friedman-Robertson-Walker cosmological model of the universe. In order to explain the discrepancy within the context of General Relativity, a new component of the energy density of the universe, known as Dark Energy (vacuum energy), with exotic properties is usually introduced, and also some other non-standard alternatives are considered. In the framework of the relativity with a preferred frame, the deceleration parameter in the luminosity distance - redshift relation is corrected such that the observed deceleration parameter can be negative. Thus, the observed negative values of the deceleration parameter do not exclude the Friedman dynamics corresponding to the matter-dominated decelerating universe.
References
[1] Burde G.I.: Special relativity kinematics with anisotropic propagation of light and correspondence principle. Found. Phys., Vol. 46, No 12, Pages: 1573-1597
Finding evidence supporting the existence of exotic states is one of the most exciting aspects of modern hadron physics. In contrast to the meson sector, the existence of exotic baryons is much more controversial, especially since the unprecedented episode of the rise and fall of the $uudd\bar{s}$ pentaquark. Recently though, the matter of pentaquarks has been resurrected by the observation of a $c\bar{c}uud$ pentaquark as claimed by the LHCb collaboration. Although there are arguments favoring the inclusion of heavy quarks in stable pentaquarks, the question remains if such and other exotic states could also be formed by $u$, $d$ and $s$ quarks only.
The tagged-photon beam experiment A2 at the MAMI electron accelerator facility in Mainz (Germany) allows the study of several photoproduction reactions in which exotic baryons could be involved in. A selection of current activities and recent results will be discussed: In $\eta$ photoproduction off the neutron, the presence of an unusually narrow resonance is one possible explanation for a sharp structure observed in the total cross section. Recently, new insights could be gained by the measurement of spin-dependent cross sections. Experimental data allowing to search for an exotic state in the $KN$ system of $\gamma d\to\Lambda KN$ are also available and undergoing analysis. Furthermore, preliminary results of a search for the dibaryon supposedly discovered by the WASA-at-COSY collaboration were obtained. Finally, a newly approved experiment dedicated to the study of the $\Lambda(1405)$ will be presented.
A new Facility for Antiproton an Ion Research (FAIR) is being build at GSI in Darmstadt, where PANDA (antiProton Annihilations at Darmstadt) will be one of the key experiments. The versatile PANDA detector together with the usage of an intense and high quality antiproton beam provides a unique environment to study the formation of hadrons and the dynamics of color confinement. As the fundamental theory of strong interactions, QCD allows a large variety of color-singlet states, thereby predicting the existence of hadrons that differ from baryons and mesons. The field of hadron physics has been intensively studied for quite a long time to predict these exotic, non-conventional forms of matter and identify them experimentally. However the agreement is not yet satisfactory, since many predictions lack in experimental evidences, and many of the recent observations in the charmonium region either were unexpected or have unexpected properties. The unique features of PANDA provide complementary tools to address the properties of recently discovered exotic candidates and to probe regimes that have not been explored yet. In this talk, I will address the unique features of PANDA and discuss a few feasibility studies that serve as benchmarks of PANDA's capabilities in the field of exotic hadron spectroscopy.
In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we make a comparison of the behaviour of continuous variable quantum correlations (quantum entanglement, entropic quantum discord, geometric quantum discord, quantum steering) for a system consisting of: 1) two non-coupled; 2) two coupled bosonic modes embedded in a common environment of the form of a thermal bath or of a squeezed thermal bath. We solve the Markovian master equation for the time evolution of the considered system and describe the quantum correlations in terms of the covariance matrix for Gaussian input states. Depending on the values of the parameters characterizing the initial state of the system (squeezing parameter, average photon numbers), the coefficients describing the interaction of the system with the reservoir (temperature, dissipation constant), and the intensity of the interaction between the two modes, one may notice phenomena like generation of quantum correlations, their suppression (sudden death), periodic revivals and suppressions, or an asymptotic decay in time of quantum correlations.
Einstein-Podolsky-Rosen steerability of quantum states is a property that is different from entanglement and Bell nonlocality. We describe the time evolution of a recently introduced measure that quantifies steerability for arbitrary bipartite Gaussian states in a system consisting of two bosonic modes embedded in a common squeezed thermal environment.
We work in the framework of the theory of open systems. If the initial state of the subsystem is taken of Gaussian form, then the evolution under completely positive quantum dynamical semigroups assures the preservation in time of the Gaussian form of the states.
It was shown that the thermal noise and dissipation introduced by the thermal environment destroy the steerability between the two bosonic modes. In the case of the squeezed thermal bath we show the dependence of the Gaussian steering on the squeezing parameters of the bath and of the initial state of the system. A comparison with other quantum correlations for the same system shows that, unlike Gaussian quantum discord, which is decreasing asymptotically in time, the Gaussian quantum steerability suffers a sudden death behaviour, like quantum entanglement.
The physical content and some implementations of the semi-microscopic models, which are able to describe the high-energy single-quasiparticle and particle-hole-type nuclear excitations in medium-heavy mass spherical nuclei, are presented in this report. The particle-hole dispersive optical model, developed recently [1], is mainly discussed. Being an extension of the standard and non-standard continuum-RPA versions to a phenomenological (and in average over the energy) consideration of the spreading effect, the model possess a set of unique possibilities in description of the high-energy particle-hole-type nuclear excitations. This set includes the description: of the particle-hole strength distribution in a wide excitation-energy interval, which includes distant “tails” of giant resonances; of the double transition density, which determines the corresponding hadron-nucleus inelastic scattering cross sections; of direct-nucleon-decay properties of the mentioned excitations and related phenomena. Some implementations of the model [2, 3] are presented together with current results concerned with charge-exchange excitations.
As applied to description of deep-hole states, formulation of the single-quasiparticle dispersive optical model in terms od corresponding Green functions [4] is discussed. Such a method allows one to propose an unitary version of the model. This version is employed for a quantitative estimation of the spreading (dispersive) contribution to the optical-model potential.
This work is partially supported by RFBR (grant No. 15-02-08007).
List of references:
I will discuss relativistic nuclear field theory (RNFT) as a novel approach to the nuclear many-body problem, which is based on QHD meson-nucleon Lagrangian and relativistic field theory. RNFT connects consistently the high-energy scale of heavy mesons, the medium-energy range of pion, and the low-energy domain of emergent collective vibrations (phonons) [1]. Mesons and phonons build up the effective interaction in various channels, in particular, the phonon-exchange part takes care of the retardation effects, which are of great importance for the fragmentation of single-particle states, spreading of collective giant resonances and soft modes, quenching and beta-decay rates with significant consequences for astrophysics and theory of weak processes in nuclei.
Over the past decade, RNFT has demonstrated a very good performance in various nuclear structure calculations across the nuclear chart [1,2-4]. Recent progress on the response theory in the proton-neutron channel [5] has allowed a very good description of spin-isospin-flip excitations, which are formed predominantly by pions coupled to proton-neutron configurations in nuclear medium. Such excitations as, for instance, Gamow-Teller and spin-dipole resonances in medium-mass nuclei are of a high astrophysical importance as they are in the direct relation to beta-decay and electron capture rates. More exotic isospin-flip excitations studied lately at NSCL facility have been described very well by RNFT [6]. Presently, excitation modes in the deuteron transfer channel are considered in view of their role in mediating the isoscalar pairing and discussed as constraints for the delta-meson contribution to the nuclear forces [7].
[1] E. Litvinova and P. Ring, Ch. 11 in Relativistic Density Functional for Nuclear Structure, ed. J. Meng (World Scientific, 2016).
[2] E. Litvinova, P. Ring, and V. Tselyaev, Phys. Rev. C 78, 014312 (2008).
[3] J. Endres, E. Litvinova, D. Savran, et al., Phys. Rev. Lett. 105, 212503 (2010).
[4] E. Litvinova, Phys. Rev. C 85, 021303(R) (2012).
[5] E. Litvinova, B.A. Brown, D.-L. Fang, T. Marketin, and R.G.T. Zegers,
Phys. Lett. B 730, 307 (2014). C. Robin and E. Litvinova, Eur. Phys. J. A 52, 205 (2016).
[6] M. Scott et al., Phys. Rev. Lett. 118, 172501 (2017); K. Miki et al., Phys. Lets. B 769, 339 (2017).
[7] E. Litvinova, C. Robin, and I.A. Egorova, arXiv:1612.09182.
We overview the physics of magnetic Bose condensation and demonstrate
how the Bose condensation and the "asymptotic freedom" of magnons manifests
itself in a vicinity of a quantum critical point. These effects have been already
observed experimentally and also in Quantum Monte Carlo lattice simulations.
We present a comparison of theory and observations.
Finally we predict an ultranarrow (long life time) Higgs excitation in
the magnetic Bose condensate phase.
SBND (Short-Baseline Near Detector) is a 112 ton liquid argon TPC neutrino detector under construction on the Fermilab Booster Neutrino Beam. Together with MicroBooNE and ICARUS-T600, SBND will search for short-baseline neutrino oscillations in the 1 eV^2 mass range. SBND will also perform detailed studies of the physics of neutrino-argon interactions, thanks to a data sample of millions of electron and muon neutrino interactions. Finally SBND plays an important role in the on-going R&D effort to develop the LArTPC technology, testing several technologies that can be used in a future kiloton-scale neutrino detectors for a long-baseline experiment. I will discuss the detector design, its current status, and present the physics program.
The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each of the 2808 LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detector and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC center of mass energy of 13 TeV with only 25 ns bunch-spacing. While LUCID-1 used gas as a Cherenkov medium, the LUCID-2 detector is in a new unique way using the quartz windows of small photomultipliers as the Cherenkov medium. The main challenge for a luminometer is to keep the efficiency constant during years of data-taking. LUCID-2 is using an innovative calibration system based on radioactive 207 Bi sources deposited on the quartz window of the readout photomultipliers. This makes it possible to accurately monitor and control the gain of the photomultipliers so that the detector efficiency can be kept stable at a percent level. A description of the detector and its readout electronics will be given, as well as preliminary results on the ATLAS luminosity measurement and related systematic uncertainties.
Profiting of the favourable conditions offered by the Gran Sasso underground laboratory and of the several low-background DAMA set-ups, many and competitive results have been obtained. In particular, this talk will review the main DAMA searches on double beta decays, on other rare decays and transitions and on some investigation on matter stability. Moreover, perspectives of a complementary investigation on Dark Matter by exploiting the directionality approach (which is sensitive to Dark Matter candidates inducing nuclear recoils) with the anysotropic ZnWO4 scintillators, will be introduced.
With the world's largest sample of J/Psi events accumulated at the BESIII detector, a few new observations were reported in recent years. In this talk,
the progress on the light exotic candidates and the prospective are highlighted.
We investigate the decays of the charmed baryons aiming at the systematic understanding of hadron internal structures based on the quark model by paying attention to heavy quark symmetry. We evaluate the decay widths from the pion emission for the known excited $\Lambda_c^*$ (Lc(2595), Lc(2625), Lc(2765), Lc(2880), Lc(2940)) baryons. We find that we can explain the decay widths of the low-lying $\Lambda_c^*$ and also predict those for higher excited $\Lambda_c^*$. It is interesting that, however, the large decay width of Lc*(2765) cannot be explained by a simple quark model.
Such systematic studies by the quark model help us not only to understand their structures but also to establish the nature of exotic hadrons beyond the conventional quark model descriptions.
[Refs]
Heavy quark hadrons are subject to recent interests due to discoveries of new exotic states. To understand their properties with suitable constituents, production and decay reactions are useful. In my talk, I will discuss reaction mechanisms for possible future J-PARC experiments. First example is the pion induced Pc productions based on the Reggeon reaction mechanism. We discuss the cross sections depending on the coupling of Pc to relevant hadronic channels. Another example is the charmed baryon productions. Assuming a simple reaction mechanism we find characteristic selection rules among various production rates depending on the internal structure of the charmed baryons. Such analysis is useful to specify the internal degrees of freedom in hadrons.
I will introduce two activities on hadron spectroscopy at J-PARC.
(I) Since the $\Lambda(1405)$ hyperon is located just below the $\bar{K}N$ threshold,
it is said that $\Lambda(1405)$ is a deeply bound $\bar{K}N$ state.
There is a long standing argument if $\Lambda(1405)$ has
a so-called double pole structure [1,2,3]. In particular, a chiral
unitary model calculation claims that a pole coupled to the $\bar{K}N$ state
is located at around 1426 MeV [2]. In order to confirm this pole structure,
we propose an experimetal study to measure the $\bar{K}N\rightarrow\pi\Sigma$ scattering
below the $\bar{K}N$ threshold via the $(K^-,n)$ reaction on a deuterium target
at the J-PARC K1.8BR Beam Line [4]. Since the $d(K^-,n)X$ reaction is expected
to enhance the S-wave $\bar{K}N\rightarrow\pi\Sigma$ scattering even below the $\bar{K}N$ threshold,
the spectral shapes provide information on $\Lambda(1405)$ coupled to the $\bar{K}N$ state.
We measured pion-Sigma missing mass spectra in the $d(K^-,n)X$ reactions
in all possible isospin final states.
We will present the spectral shapes and discuss the nature of $\Lambda(1405)$.
(II) Baryons comprized with two light quarks and a heavy quark, such as charmed baryons,
provide unique opportunities to learn diquark correlations in a baryon.
It is important to investigate how quark correlations, such as
diquark and/or hadron clusters, are developped inside hadrons
in order to understand structure of exotic hadrons.
We are planning to construct a new platform on precision spectroscopy
of excited charmed baryons by using a high-resolution, high-momentum, intense pion beam
provided at the High-momentum Beam Line at J-PARC [5].
Masses, widths, decay branching ratios, and production/formation cross sections
of excited charmed baryons reflect their internal structure.
We will measure them by means of missing mass techniques via the $p(\pi^-,D^{*-})$ reaction.
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Nucl. Phys. A725, 181(2003).
[3] T. Hyodo and W. Weise, Phys. Rev. C77, 035204 (2008).
[4] H. Noumi et al., J-PARC E31 Proposal, 2009.
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The firm understanding of standard quark-antiquark states (including excited states) is necessary to perform search of non-conventional mesons with the same quantum numbers. In this talk, we study the phenomenology of two nonets of excited vector mesons, which predominantly correspond to radially excited vector mesons with quantum numbers $n \hspace{0.15cm} ^{2s+1}L_{J} = 2 ^{3}S_{1}$ and to orbital excited vector mesons characterised by quantum numbers $n \hspace{0.15cm} ^{2s+1}L_{J} = 1 ^{3}D_{1}$. We evaluate the decays of these mesons into two pseudoscalar mesons and into a pseudoscalar and ground-state vector meson by making use of a relativistic quantum field theoretical model which based on flavor symmetry. Moreover, we also study the radiative decays into a photon and a pseudoscalar mesons by using vector meson dominance. We shall compare our results to the PDG and comment on open issues concerning the corresponding measured resonances. Within our approach, we are also able to make predictions for a not-yet discovered $\bar{s}s$ state in $n \hspace{0.15cm} ^{2s+1}L_{J} = 1 ^{3}D_{1}$ nonet which has the mass of about 1.93 GeV. This resonance can be searched in the upcoming Gluex and Mesonex experiments which take place at Jefferson lab.
We analyse, within a dipole model, the final, inclusive HERA DIS cross section
data in the low x region, using fully correlated errors. We show, that these h
ighest precision data are very well described within the dipole mod
el framework starting from Q2 values of 3.5 GeV2 to the highest values of
Q2= 250 GeV2. To analyze the saturation effects we evaluated the data includ
ing also the very low 0.35 < Q2GeV2 region. The fits including this region
show a preference of the saturation ansatz.
Published in Phys.Rev. D95 (2017) no.1, 014030
Entanglement measures proved to be a vital tool for
development of quantum information science. For example, an important
property of entanglement called monogamy is quantitative, and therefore
cannot be captured without introducing entanglement measures.
Additionally, entanglement measures provide useful bounds on several
important hardly computable quantities, and they are indispensable in
proofs of some quantum-information no-go theorems. In experiment,
entanglement measures are needed to assess the quality of prepared
entangled states and entangling gates, and they set bounds one has to
surpass to demonstrate some crucial quantum protocols such as
entanglement distillation.
A common feature of a vast majority of currently used entanglement
measures is that either they possess a good physical meaning or are
computable but not both. We probe the gap between computable and
physically meaningful entanglement measures by introducing a new
quantifier of entanglement which we call intrinsic entanglement
(IE) [1,2]. The proposed quantity is a modification of the so called
classical measure of entanglement [3], which is obtained by maximin
optimization of intrinsic information [4] giving an upper bound on the
secret-key rate in the classical secret key agreement protocol [5].
We investigate the IE within the framework of an important class
of Gaussian states, operations, and measurements. We show, that in
the Gaussian scenario IE simplifies to the mutual information of a
Gaussian distribution of outcomes of measurements on parts of the system,
conditioned on the outcomes of a measurement on a purifying subsystem,
which is first minimized with respect to measurements on the purifying
part and subsequently maximized over the remaining measurements. It is
further demonstrated that the Gaussian intrinsic entanglement
(GIE) vanishes only on separable states and it exhibits monotonicity under
Gaussian local trace-preserving operations and classical communication.
Finally, in the case of two-mode states we compute GIE for all pure states,
all symmetric states with a three-mode purification, asymmetric squeezed
thermal states with a three-mode purification and restricted local noises, as
well as for symmetric squeezed thermal states with a four-mode purification
and restricted local noises. Surprisingly, in all of these cases, GIE is
equal to Gaussian Rényi-2 entanglement [6], which leads us to a conjecture
that the two quantities are equal on all Gaussian states. As GIE is
operationally associated to the secret-key agreement protocol and can
be computed for several important classes of states, it offers a compromise
between computable and physically meaningful entanglement quantifiers.
References:
[1] L. Mišta, Jr. and R. Tatham, Gaussian Intrinsic Entanglement, Phys.
Rev. Lett. 117, 240505 (2016).
[2] L. Mišta, Jr. and R. Tatham, Gaussian intrinsic entanglement: An
entanglement quantifier based on secret correlations, Phys. Rev. A 91,
062313 (2015).
[3] N. Gisin and S. Wolf, Linking Classical and Quantum Key Agreement:
Is There "Bound Information"?, in Proceedings of CRYPTO 2000, Lecture
Notes in Computer Science 1880 (Springer, Berlin, 2000) p. 482.
[4] U. M. Maurer and S. Wolf, Unconditionally secure key agreement and
the intrinsic conditional information, IEEE Trans. Inf. Theor. 45, 499
(1999).
[5] U. M. Maurer, Secret Key Agreement by Public Discussion from Common
Information, IEEE Trans. Inf. Theor. 39, 733 (1993).
[6] G. Adesso, D. Girolami, and A. Serafini, Measuring Gaussian Quantum
Information and Correlations Using the Rényi Entropy of Order 2, Phys.
Rev. Lett. 109, 190502 (2012).
As quantum technologies develop the question of verifying/certifying the correctness of the quantum devices is crucial. In particular, as quantum computers will outperform classical, it may be impossible to test the correctness of the quantum computer using a classical. Instead, one need to perform verifiable quantum computation (VBQC). A number of such protocols exist, and we focus on protocols that exploit blind quantum computation (e.g. Fitzsimons, Kashefi 2012). For those protocols the (honest) parties need to trust their devices. We developed a protocol that is device independent (Gheorghiu, Kashefi, Wallden 2015), however that protocol similarly to other works (e.g. Reichardt, Unger, Vazirani 2012) impose an unphysical assumption of no-communication between parties that cannot be enforced using spacelike separation. In this contribution we develop a protocol that avoids this problem by first formulating the VBQC in a "step-wise" form and then giving a truly device-independent protocol where the no-communication of the parties is enforced from relativistic constraints.
Modern cryptography covers much more than encryption of messages in order to keep them secret. Many other cryptographic primitives exist, and it is important to consider how the security of these will be affected in a quantum future. Digital Signatures are a widely used cryptographic primitive, found eg. in e-mail, e-commerce and digital banking, and they form the basis for larger protocols. A signature $\sigma_m$ appended to a classical message $m$ ensures the authenticity and transferability of the message, whilst preventing forgery and repudiation. By employing quantum mechanics to distribute the $\sigma_m$ between recipients, unconditionally secure signature schemes can be constructed [1-4].
As the development of quantum security progresses, one must consider how to implement these schemes using currently existing technology.
To this end, we present a continuous-variable quantum signature scheme with an emphasis on compatibility with existing telecommunication technologies. Our scheme is information-theoretically secure against repudiation attacks and collective forging attacks, and can be implemented even when some QKD-based signature protocols fail. We note that this is the first implemented continuous-variable quantum signature scheme which does not require secure quantum channels between participants, although discrete-variable protocols have been proposed and implemented [5-6].
In the simplest scenario, quantum digital signature (QDS) schemes involve three parties: Alice, who wishes to sign $m$, and two recipients, Bob and Charlie. In a Distribution stage, Alice forms sequences of quantum states, $\rho_{B}^m$ and $\rho_C^m$, and sends them to Bob and Charlie, who measure the states and record their outcomes. The quantum states can be thought of as Alice's public key''. Her corresponding
private key'', containing classical information about which states she sent, is used as the signature $\sigma_m$. Crucially, since a QDS scheme relies on quantum measurement, recipients gain only partial information about $\sigma_m$. Later, in an entirely classical Messaging stage Alice sends $\left(m, \sigma_m\right)$. Bob and Charlie compare $\sigma_m$ to their measurement results, and accept or reject $m$ accordingly.
We have implemented our scheme by distributing an alphabet of phase-modulated coherent states over a $20$~km optical fiber, and have devised the corresponding security proof. In particular, we prove that a dishonest forger who interacts with the quantum states cannot then declare some $\sigma'_m$ which will be accepted by honest recipients, except with negligible probability (security against forging). The probability of successful forgery is related to the smooth min-entropy, which can be interpreted as the uncertainty that an eavesdropper has about an honest participant's measurement outcomes [7]. Hence, by estimating a lower bound for the smooth min-entropy we prove security of our protocol, considering the finite-size effects intrinsic to signatures. As tighter bounds are developed these can readily be incorporated. Furthermore, Bob's and Charlie's measurement outcomes are symmetrised with respect to Alice, which makes it unlikely that a dishonest Alice can find some $\sigma''_m$ which Bob will accept but that she can later deny sending (security against repudiation).
Our system is built from telecom components running at a wavelength of $1553.33$~nm and is completely fiber-integrated. The coherent states are distributed by Alice at a rate of $10$~GHz and are measured using homodyne detection at Bob/Charlie. With our security proof the signature lengths are of the order of $10^6$ to sign $m$ with a $0.01\%$ chance of failure, meaning a $1$~bit message can be signed in $0.1$~ms. This opens the possibility of efficiently distributing quantum signatures on a large scale with minimal installation cost, and makes our scheme competitive in a landscape where both practicality and security are important.
[1] D. Gottesman and I. Chuang, “Quantum Digital Signatures,” 0105032 [quant-ph]
[2] R. J. Collins, R. J. Donaldson, V. Dunjko, P. Wallden, P. J. Clarke, E. Andersson, J. Jeffers, and G. S. Buller, Phys. Rev. Lett. 113, 040502 (2014)
[3] V. Dunjko, P. Wallden, and E. Andersson, Phys. Rev. Lett. 112, 040502 (2014)
[4] C. Croal, C. Peuntinger, B. Heim, I. Khan, C. Marquardt, G. Leuchs, P. Wallden, E. Andersson, and N. Korolkova, Phys. Rev. Lett. 117, 100503 (2016)
[5] R. Amiri, P. Wallden, A. Kent, and E. Andersson, Phys. Rev. A 93, 032325 (2016)
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[7] R. König, R. Renner, and C. Shaffner, IEEE Trans. Inf. Theory 55, 4337 (2009)
Continuous Variables are a promising platform for demonstrating large scale quantum information effects thanks to the experimental advantages they provide. In this framework, we define a general quantum computational model based on a continuous variables hardware. It consists in vacuum input states, a finite set of gates — including non-Gaussian elements — and homodyne detection. We show that this model enables the encoding of fault tolerant universal quantum computing. Furthermore, when restricted to only commuting gates it turns into a sampling problem that can’t be simulated efficiently with a classical computer — unless the polynomial hierarchy collapses. Thus we provide a simple paradigm for short-term experiments relying on Gaussian states, homodyne detection and some form of non-Gaussian evolution.
The alleged wave-function collapse becomes especially intriguing when detection does not occur (IFM), nevertheless exerting causal, even nonlocal effects. How can a non-event be causally equivalent to an actual one? Our answer is based of two recent advances. i) Quantum Oblivion [1-4] is a basic quantum interaction recently discovered, showing that even non-events are events which very briefly occur and then “unoccur” prior to the final macroscopic collapse. ii) The Two-State-Vector Formalism (TSVF) [5] renders the quantum interaction a combination of two wave-functions going along both time directions. A recent prediction [6,7] of this formalism, verifiable with ordinary quantum measurements, obliges the disappearance and reappearance of a particle under special conditions. The former occurs when the particle and its counterpart, possessing negative mass (nega-particle) occupy the same spacetime region, while the latter follows when they are apart again. These two lines of investigation suggest a simple and natural account of many quantum phenomena.
References
[1] A.C. Elitzur, E. Cohen, Int. J. Quantum Inf. 12, 1560024 (2015).
[2] E. Cohen, A.C. Elituzr, J. Phys.: Conf. Ser. 626 012013 (2015).
[3] A.C. Elitzur, E. Cohen, Philos. T. Roy. Soc. A 374, 20150242 (2016).
[4] Y. Aharonov, E. Cohen, A.C. Elitzur, L. Smolin, arXiv:1610.07169.
[5] Y. Aharonov, L. Vaidman, The Two-State Vector Formalism of Quantum Mechanics, in Time in Quantum Mechanics, J.G. Muga et al. (eds.), Springer, 369-412 (2002).
[6] Y. Aharonov, E. Cohen, A. Landau, A.C. Elitzur, Sci. Rep. 7, 531 (2017).
[7] Y. Aharonov, E. Cohen, A.C. Elitzur, R. Okamoto, S. Takeuchi, Nonlocal position changes of a particle under special pre- and post-selection, revealed by strong measurements and proved by Bell's theorem, forthcoming.
The antinucleon-nuclei annihilation cross sections at low energies were systematicaly measured at CERN in the 80's and 90's with the LEAR facility and later with the Antiproton Decelerator. Unfortunately only few data exist for very low energy antiprotons (p<500 MeV/c) on medium and heavy nuclei.
A deeper knowledge is required by fundamental physics and can have consequence also in cosmology and medical physics.
In order to fill the gap, the ASACUSA Collaboration has very recently measured the annihilation cross section of 100 MeV/c antiproton on carbon.
In the present work the experimental result is presented together with a comparison both with the antineutron data on the same target at the same energies and with the other existing antiproton data at higher energies.
An exact solution to the heat equation in curved space is a much sought after; this report presents a derivation wherein the cylindrical symmetry of the metric in 3 + 1 dimensional curved space has a pivotal role. To elaborate, the spherically symmetric Schwarzschild solution is a staple of textbooks on general relativity; not so perhaps, the static but cylindrically symmetric ones, though they were obtained almost contemporaneously by H.Weyl,Ann.Phys.Lpz.54,117(1917)
and T. Levi-Civita, Atti Acc. Lincei Rend. 28,101(1919). A renewed interest in this subject recently in C.S. Trendafilova and S.A. Fulling ,Eur.J.Phys. 32,1663(2011) – to which the reader is referred to for more references –
motivates this work, the first part of which (cf.Kamath, PoS (ICHEP2016)791) reworked the Antonsen-Bormann idea – arXiv:hep-th/9608141v1 – that was originally intended to compute the heat kernel in curved space to determine – following D.McKeon and T.Sherry,Phys.Rev.D35,3584(1987) – the zeta-function associated with the Lagrangian density for a massive real scalar field theory in 3 + 1 dimensional stationary curved space to one-loop order, the metric for which is cylindrically symmetric. Using the same Lagrangian density the
second part reported here essentially revisits the second paper by Bormann and Antonsen – arXiv:hep 9608142v1 but relies on the formulation by the author in S.G.Kamath, AIP Conf.Proc.1246,174 (2010) to obtain the Green’s function directly by solving a sequence of first order partial differential equations that is preceded by a second order partial differential equation.
The interaction of very low energy $\bar{p}$ and $\bar{n}$ with nuclei is interesting for its influence on both fundamental cosmology and nuclear physics. Measuring the annihilation cross section of antimatter on matter can help in solving the universe matter-antimatter puzzle and could give relevant hints in the definition of strong interaction model parameters as well.
The ASACUSA collaboration recently measured the antiproton-carbon annihilation cross section at 5.3~MeV of kinetic energy of the incoming antiproton. The experimental apparatus consisted in a vacuum chamber containing thin foils ($\sim$0.7--1~$\mu$m) of carbon crossed by a bunched beam of antiprotons from the CERN Antiproton Decelerator (AD). The fraction of antiprotons annihilating on the target nucleons gives origin to charged pions which can be detected and counted by segmented scintillators placed outside the chamber. This work describes the experimental details of the apparatus and the technique to perform the cross section measurements.
We discuss nonempty space physics of material fields in the 1938 interpretation of Einstein and Infeld. The extended carrier of radial energies contains chaotic motions of material densities associated to the rest mass-energy or internal relativistic heat. Chaotic (internal) and ordered (translation) kinetic energies tend to equal values under the free gravitational fall. This universal tendency of any falling body to equipartition of its relativistic kinetic energies can shed a new light on the cyclic geodetic motion and on the periodic evolution of multi-body systems.
Thermal radiation/absorption can vary geodesic paths of free bodies. Einstein’s relativistic dynamics of full energies incorporates variable heat of real thermodynamic bodies even at low speeds. The Newton model of masses without temperature cannot be a true nonrelativistic limit for SR/GR references. We explain quantitatively why “Einstein's theory can be accepted only with the recognition that Newton's was wrong.” (S. Kuhn. The Structure of Scientific Revolutions, 1962, p.98).
Quantum key distribution (QKD) [1] is a technique that allows distribution of a secret random bit string between two separated parties (Alice and Bob). In theory, QKD provides information-theoretic security based on the laws of quantum physics. In practice, however, it does not, as standard QKD realizations cannot typically fulfill the demands imposed by the theory. As a result, any unaccounted device imperfection might constitute a side-channel which could be used by an eavesdropper (Eve) to extract the secret key without being detected. To bridge this gap, various approaches have been proposed, with measurement-device-independent QKD (mdiQKD) [2] probably being the most promising one in terms of feasibility and performance. Compared to standard prepare-and-measure QKD schemes [1], its security is based on post-selected entanglement. This allows to remove all detector side-channels from QKD implementations. Also, its practicality has been already confirmed both in laboratories and via field trials [3, 4]. However, one drawback of mdiQKD is that it requires high-visibility two-photon interference between independent sources, which makes its implementation more demanding than that of standard prepare-and-measure QKD schemes. Another limitation is its security proofs require larger post-processing data block sizes than those of standard QKD.
To overcome these limitations, a novel approach, so-called detector-device-independent QKD (ddiQKD), has been introduced recently [5–8]. It avoids the problem of interfering photons from independent light sources by using the concept of a single-photon Bell state measurement (BSM) [9]. As a result, it achieves the robust security of MDI-QKD, and at the same time provides the ease of implementation like standard prepare-and-measure QKD schemes. Also, its post-processing data block sizes are expected to be similar to those of standard prepare-and-measure QKD schemes [10]. To summarize, DDI-QKD was assumed to become the 'holy grail' of quantum key distribution protocols.
In this talk, I will show that, although it is widely assumed that DDI-QKD is robust to detector side-channels, it is in practice not true. Our main contributions are twofold. First, we show that, in contrast to mdiQKD, the security of ddiQKD cannot be based on post-selected entanglement alone, as initially thought in [5–8]. Hence, its security is not as robust as MDI-QKD. Second, we show that DDI-QKD is actually insecure against detector side-channel attacks by presenting various eavesdropping strategies that can fully compromise the security of the system.
The manuscript can be found at:
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.250505
[1] C. H. Bennett and G. Brassard, in Proc. IEEE International Conference on Computers, Systems, and Signal Processing (Bangalore, India) (IEEE Press, New York, 1984) pp. 175– 179.
[2] H.-K. Lo, M. Curty, and B. Qi, Phys. Rev. Lett. 108, 130503 (2012).
[3] Y.-L. Tang, H.-L. Yin, Q. Zhao, H. Liu, X.-X. Sun, M.- Q. Huang, W.-J. Zhang, S.-J. Chen, L. Zhang, L.-X. You, Z. Wang, Y. Liu, C.-Y. Lu, X. Jiang, X. Ma, Q. Zhang, T.- Y. Chen, and J.-W. Pan, Phys. Rev. X 6, 011024 (2016).
[4] H.-L. Yin, T.-Y. Chen, Z.-W. Yu, H. Liu, L.-X. You, Y.- H. Zhou, S.-J. Chen, Y. Mao, M.-Q. Huang, W.-J. Zhang, H. Chen, M. J. Li, D. Nolan, F. Zhou, X. Jiang, Z. Wang, Q. Zhang, X.-B. Wang, and J.-W. Pan, Phys. Rev. Lett. (in press), arXiv:1606.06821 [quant-ph].
[5] P. Gonz ́alez, L. Rebo ́n, T. Ferreira da Silva, M. Figueroa, C. Saavedra, M. Curty, G. Lima, G. B. Xavier, and W. A. T. Nogueira, Phys. Rev. A 92, 022337 (2015).
[6] C. C. W. Lim, B. Korzh, A. Martin, F. Bussi`eres, R. Thew, and H. Zbinden, Appl. Phys. Lett. 105, 221112 (2014).
[7] W.-F. Cao, Y.-Z. Zhen, Y.-L. Zheng, Z.-B. Chen, N.-L. Liu, K. Chen, and J.-W. Pan, manuscript withdrawn by au- thors on 23 Aug 2016 owing to the insecurity of the proposed scheme, arXiv:1410.2928v1 [quant-ph].
[8] W.-Y. Liang, M. Li, Z.-Q. Yin, W. Chen, S. Wang, X.-B. An, G.-C. Guo, and Z.-F. Han, Phys. Rev. A 92, 012319 (2015).
[9] Y.-H. Kim, Phys. Rev. A 67, 040301 (2003).
[10] C. C. W. Lim, M. Curty, N. Walenta, F. Xu, and H. Zbinden,
Phys. Rev. A 89, 022307 (2014).
The identification of jets originating from heavy flavour quarks is a crucial aspect in numerous searches at the Large Hadron Collider. In the context of the CMS experiment, a new tagger, DeepFlavour, that uses Deep Neural Networks has been developed. DeepFlavour is a multiclassifier that is found to outperform significantly other taggers used in CMS, being so far tested in simulation. This gain in performance, especially for jets with high transverse momenta, can lead to improved sensitivity for several analyses both on searches for New Physics and on Standard Model processes.
The "GeV-excess" of the diffuse gamma-rays, as observed by the Fermi-LAT satellite, is studied with a spectral template fit based on energy spectra for each possible process of gamma-ray emission. If all physical processes are included, one should be able to describe the whole gamma-ray sky in all regions, including the Galactic center, the Fermi Bubbles and the "GeV-excess". In addition to the "standard" physical processes for gamma-ray production from $\pi_0$ decays produced by diffused cosmic rays, inverse Compton scattering and Bremsstrahlung we find clear evidence for two additional processes: $\pi_0$ production in sources during acceleration and $\pi_0$ production in molecular clouds. The first one is characterized by nuclear cosmic rays with the hard $1/E^{2.1}$ spectrum, expected from diffusive shock wave acceleration. The second one is characterized by nuclear cosmic rays inside molecular clouds with a sharp cutoff below 14 GV, due to a process analogous to the geomagnetic cutoff, which is most clearly observed in the dense Central Molecular Zone encircling the Galactic center in the Galactic disk. Such a suppression of low energy nuclei leads to a shift in the maximum of the gamma-ray spectrum to higher energies, the hall-mark of the "GeV-excess". To see if this excess can indeed be explained by the propagation inside molecular clouds, one needs to check in addition the spatial distribution. Fortunately, molecular clouds can be traced by the rotation lines of the CO molecule. Furthermore, the nuclear cosmic rays can be traced by the 1.8 MeV gamma-ray line from radioactive $^{26}$Al decays, which is synthesized in sources.
The similar morphology between sources, high-energy tail in gamma-ray spectra, molecular clouds and the "GeV-excess" establishes the two new processes discussed above and provides evidence that the "GeV-excess" is produced inside molecular clouds, thus excluding the interpretation of a dark matter annihilation signal. This erroneous interpretation is easily explained by the fact that the
column density of molecular clouds resembles the spatial distribution of an annihilation signal, at least if the field-of-view is limited to a cone of less than 20$^\circ$ around the Galactic center, while the shift of the maximum of the gamma-ray energy spectrum inside molecular clouds, most likely originating from a magnetic cutoff and energy losses, resembles the spectral shape of a dark matter annihilation signal of 60 GeV dark matter particles.
Muons are of key importance to study some of the most interesting physics topics at the LHC.
We show the status of the performance of the muon reconstruction in the analysis of proton-proton
collisions at the LHC, recorded by the ATLAS detector in 2016 and 2017. Reconstruction efficiency
and momentum resolution have been measured using J/Psi and Z decays for different classes of
reconstructed muons.
We study the presence of thermodynamic instabilities in a nuclear medium at finite temperature and density where nuclear phase transitions can take place. Similarly to the low density nuclear liquid-gas phase transition, we show that such a phase transition is characterized by pure hadronic matter with both mechanical instability (fluctuations on the baryon density) that by chemical-diffusive instability (fluctuations on the strangeness concentration).
The analysis is performed by requiring the global conservation of baryon number and zero net strangeness in the framework of an effective relativistic mean field theory with the inclusion of the Delta(1232)-isobars, hyperons and the lightest pseudoscalar and vector meson degrees of freedom. It turns out that in this situation hadronic phases with different values of strangeness content may coexist, altering significantly baryon-antibaryon ratios.
This poster presents a search for heavy particles decaying into eμ final states with 13 TeV proton-proton collision data recorded with the CMS detector at the LHC. The search is interpreted using two different benchmark models. One of them is the scenario of resonant τ sneutrino production in R-parity violating supersymmetry, and the other is the non-resonant signal of Quantum Black Hole (QBH) production in models with extra dimensions.
A search for supersymmetry in events with a single electron or muon, hadronic jets and missing transverse momentum is presented. The data corespond to 35.9 fb−1 of proton-proton collisions recorded in 2016 by the CMS experiment at a center-of-mass energy of 13 TeV. The events are sorted into several exclusive search samples based on the number of jets and b-tagged jets, the scalar sum of the jet transverse momenta, and the scalar sum of the missing transverse momentum and the transverse momentum of the lepton. The numbers of events observed in all search samples are consistent with the expectations from standard model processes, and the results are used to set lower limits on superymmetric particle masses in the context of two simplified models of gluino pair production. In the first model, each gluino decays via a three- body process to a top quark-antiquark pair and a neutralino, which is assumed to escape udetected. Gluinos with masses up to 1.8 TeV are excluded for neutralino masses below 800 GeV. In the second model, each gluino decays via a three-body process to a light quark-antiquark pair and a chargino, which subsequently decays to a W boson and a neutralino. The mass of the chargino is taken to be midway between the gluino and neutralino masses. In this model, gluinos with masses below 1.9 TeV are excluded for neutralino masses below 300 GeV.
We search for x-rays from abnormal atomic orbit electron transitions that may violate the Pauli Exclusion Principle, in the VIP-2 experiment at Gran Sasso national laboratory. The candidate events come from a $2p$ electron transits into a $1s$ orbit which is occupied by two electrons. Such event, if exists, will have detectable energy difference from normal $2p-1s$ atomic transition by few hundreds of electron-volts in case it occurs in a copper atom, and the energy difference is expected to be the result of the electromagnetic shielding effect from the additional electron in the ground state.
The experimental setup with the complete detector system was mounted in the underground laboratory in 2015, and we started the physics run without the final passive lead shielding since October 2016.
From two months of data taking, we confirmed the performance of the apparatus that will fulfill the designed goal of the experiment. Moreover preliminary result from the first period of physics run already improved the upper limit set by the previous VIP experiment.
After the discovery of a Higgs boson, the measurements of its properties are at the forefront of research. The determination of the associated production of a Higgs boson and a pair of top quarks is of particular importance as the ttH Yukawa coupling is large, and thus a probe for physics beyond the Standard Model.
The ttH production was analysed in various final states
with multileptons and covering as well
$\rm H\rightarrow \gamma\gamma$ and
$\rm H\rightarrow b\bar b$.
The analysis was based on data taken by the ATLAS experiment recorded from 13~TeV proton-proton collisions.
The combined results are compared with the Standard Model (SM) expectation allowing models beyond the SM to be constrained.
The $\Lambda\Lambda$ bond energies ($\Delta B_{\Lambda\Lambda}$) of double-$\Lambda$ hypernuclei provide a measure of the nature of the in-medium strength of the $\Lambda\Lambda$ interaction. Likewise, the charge symmetry breaking in mirror nuclei with $\Lambda$ and $\Lambda\Lambda$ is expected to shed light on $\Lambda$N and $\Lambda\Lambda$N interactions. The $\Lambda\Lambda$-separation energy ($B_{\Lambda\Lambda}$) from a double-$\Lambda$ nucleus exceeds twice the value of the $\Lambda$-separation energy ($B_{\Lambda}$) of a single-$\Lambda$ nucleus and this excess is known as the bond energy given by,
$\Delta B_{\Lambda\Lambda}$=$B_{\Lambda\Lambda}$ ($^A_{\Lambda\Lambda}$Z)- 2$B_{\Lambda}$ ($^{A-1}_{\Lambda}$Z),
where A is the mass number with the hyperon number included. A generalized mass formula, constructed earlier with broken SU3 symmetry, is employed to calculate the separation energies from light to heavy nuclei. The newly available experimental data on $\Lambda\Lambda$ -separation energy of several double-$\Lambda$ nuclei, and some single-$\Lambda$ nuclei put stringent constraint on this formula leading to a modification of one of its parameters. The $B_{\Lambda}$ , $B_{\Lambda\Lambda}$ and $\Delta B_{\Lambda\Lambda}$ values calculated with this revised mass formula are in good agreement with the experimental data. Results are also compared with the recent predictions from the quark mean-field model (QMF) and the relativistic mean-field (RMF) approach. The mass formula enables prediction of the bond energy and symmetry energy for a wide range of nuclei for which experimental $\Lambda$- and $\Lambda\Lambda$-separation energy values are not yet available. Both the bond energies and the charge symmetry breaking in mirror nuclei are found to have definite A-dependence.
Inertial Confinement Fusion is a promising option to
provide massive, clean, and affordable energy for
mankind in the future. The present status of research
and development is hindered by hydrodynamical instabilities
occurring at the intense compression of the target fuel by
energetic laser beams.
We show here an analytical model.The compression of the target pellet can be negligible and rapid volume ignition is achieved by a laser pulse, which is
as short as the penetration time of the light across the pellet.
The reflectivity of the target can be made negligible, and
the absorptivity is varied so that the light pulse can reach the opposite side
of the pellet.
The short light pulse can heat the target so that most of the
interior will reach the ignition temperature simultaneously.
This prevents the development of any kind of instability, which
would prevent complete ignition of the target.
With quantum science in space we reach a regime of physics, where the interplay between general relativity and quantum theory is unclear. A contemporary experimental scenario is satellite-based quantum communication, where an investigation of the impact of gravitational effects is of both, fundamental and technological interest. Specifically, quantum field theory in curved space-time (or relativistic quantum information) is used to describe the aforementioned scenario, while experimental evidence for the predictions are not existing yet [1]. However, the rapid development of quantum technologies in space necessitates a thorough experimental investigation of the relevant physics [2, 3]. Therefore, we investigate potential realization of relativistic quantum information experiments, based on a space-to-ground quantum communication link with a satellite in the geostationary Earth orbit [4]. Thereby, we aim to complement quantum field theory in curved space-time with experimental evidence and to explore possible limitations of satellite-based quantum communication.
[1] R. Howl et al., arXiv:1607.06666 (2016).
[2] D. Rideout et al., Class. Quantum Gravity 29, 224011 (2012).
[3] G. Vallone et al., Phys. Rev. Lett. 116, 253601 (2016).
[4] K. Günthner et al., arXiv:1608.03511 (2016).
Relativistic heavy ion collisions are a unique way to form the quark gluon plasma (QGP). Measurements of the azimuthal anisotropy of particle production in relativistic heavy ion collisions have been used to study the initial condition and the relativistic hydrodynamic response of the hot and dense matter. The hydrodynamical response of the QGP to a given initial condition can be studied by selecting different collision systems. For this purpose, symmetric Au+Au/Cu+Cu and asymmetric Cu+Au collisions have been operated at RHIC, and the azimuthal anisotropy strength v_n have been measured in these collision systems.
In addition, RHIC has operated small collision systems, p/d/3^He+Au collisions which have been considered too small to form the QGP. Although a finite v_n has been considered to arise from the strong hydrodynamical expansion, recent measurements of v_n in the small collision systems at RHIC show similar strengths as seen in heavy ion collisions. Measurements of v_n in small collision systems could provide a better understanding of the hydrodynamical limit and other mechanisms which cause the large anisotropy in small collision systems.
In this poster, we will present the latest results on azimuthal anisotropies in symmetric and asymmetric heavy ion collisions as well as small colliding systems at PHENIX.
The problem about the classical limit of Quantum Mechanis is a thorny and intriguing issue at the core of modern physics. There remain many doubts about this fundamental question of the foundations of Quantum Mechanics. In the literature, there are many procedures to aboard this matter, the best known and used are the Planck´s limit ( ) and the Bohr´s Correspondence Principle (n>>1). Nathan Rosen and Richard Libboff have affirmed that this limits are not equivalent and that none of them has a universal charcater.
In this work we propose a new mathematical formulation of the Correspondence Principle. This new approach consists of obtaining the asymptotic limit of quantum probability density. As a result of this procedure, Classical Physics emerges as an asymptotic case of Quantum Mechanics. We show as examples of this procedure the cases of the quantum harmonic oscillator, the Kepler problem, the particle en the square infinity well and the quantum free falling.
With this approach one can understand the difference between the Planck´s limit and the Bohr´s Correspondence Principle. It also allows to clarify some of the differences that exist between Quantum Mechanics al Classical Physics.
The size distribution of geometrical spin clusters is exactly found for the one-dimensional Ising model of finite extent. For the values of lattice constant ?$\beta$ above some “critical value” $\beta_c$ the found size distribution demonstrates the non-monotonic behavior with the peak corresponding to the size of the largest available cluster. In other words, for high values of the lattice constant there are two ways to fill the lattice: either to form a single largest cluster or to create many clusters of small sizes. This feature closely resembles
the well-know bimodal size distribution of clusters which is usually interpreted as a robust signal of the first order liquid-gas phase transition in finite systems. It is remarkable that the bimodal size distribution of spin clusters appears in the one-dimensional Ising model of finite size, i.e. in the model which in thermodynamic limit has no phase transition at all.
Supersymmetry is undoubtedly a popular candidate for physics beyond the Standard Model. However, the origin of soft supersymmetry breaking masses has been usually depicted intricately in the literature via extra hidden/mediating sectors. Thus, a simple theory for the generation of the soft masses would be more compelling. Recently, our group discussed in two sequential papers a new approach to dynamical supersymmetry breaking via Nambu--Jona-Lasinio Model, which has been missed since the first investigation of supersymmetric NJL model. We introduce a four-superfield interaction term that induces a real two-superfield composite with vacuum condensate. The latter has supersymmetry breaking parts, which we show to bear nontrivial solutions following a standard nonperturbative analysis for a NJL type model. In the talk, I will discuss this possibility of dynamical supersymmetry breaking, and present the prototype model, with the analysis of effective theory picture. The presence of the expected Goldstino along with the supersymmetry breaking will be also demonstrated.
The time evolution of the strongly interacting matter created in a heavy-ion collision depends on the initial geometry and the collision centrality. This makes important the experimental determination of the collision geometry. In this presentation a procedure for event classification and estimation of the geometrical parameters in inelastic Pb-Pb collisions at the beam energy of 40 AGeV recorded with the fixed target experiment NA49 at CERN SPS is discussed. In the NA49 experiment, event classes can be defined using measured multiplicity of particles in the Time Projection Chamber (TPC) or energy of spectators deposited in forward Veto or Ring calorimeters. Using the Monte-Carlo Glauber model, these event classes can be related to average values of the geometric quantities such as impact parameter or number of nucleon-nucleon collisions.The implementation of this procedure within a software framework of the future CBM experiment was adopted for event classification in the NA49 experiment. In the future, this procedure will be used for analysis of the new Pb-Pb data collected by the NA61/SHINE experiment and for comparison with the results previously obtained by STAR at RHIC and the NA49 at CERN SPS Collaborations.
We seek to construct a quantum theory of hypercomplex fields, the
commutative ring of hypercomplex numbers allows us to have as internal symmetry U(1)xS0 (1,1). The hypercomplex fields encode information fields two charged particle. Normal ordering is not requiered to control the divergence of the vacuum.
Several possible extensions of the Standard Model predict the existence of a dark sector that is weakly coupled to the visible one: i.e. the two sectors couple via the vector portal, where a dark photon with mass in the MeV to GeV range mixes kinetically with the SM photon. If the dark photon is the lightest state in the dark sector, it will decay to SM particles, mainly to leptons and possibly light mesons. Due to its weak interactions with the SM, it can have a non-negligible lifetime. At the LHC, these dark photons would typically be produced with large boost resulting in collimated jet-like structures containing pairs of leptons and/or light hadrons, the so-called lepton-jets (LJs).
This work is focused on the search for â€œdisplaced LJsâ€, which are produced away from the interaction point and their constituents are limited to electrons, muons, and pions. The requested topology includes one or two LJs + leptons/jets/MET. The most recent ATLAS results based on samples collected at a center of mass energy of 13 TeV will be presented.
Results are interpreted in terms of the Falkowsky-Ruderman-Volansky-Zupan models where dark photons are generated through the decay of a Higgs boson to intermediate hidden fermions. The Higgs boson is supposed to be produced via gluon-fusion and for the first time, results are also presented in terms of the associated production of a Higgs boson with a W/Z and in the context of inelastic thermal relic dark matter.
In this paper, S.M.T. (Surrounding Matter Theory), an alternative theory to dark matter, is presented. It is based on a modification of Newton’s law. This modification is done by multiplying a Newtonian potential by a given factor, which is varying with local distribution of matter, at the location where the gravitational force is exerted. With this new equation the model emphasizes that a gravitational force is roughly inversely proportional to mass density at the location where this force is applied. After presentation of the model, its dynamic is quickly illustrated by cosmology. Some possible caveats of the model are identified. But the simple mechanism described above suggests the idea of a solution to the following issues: virial theorem mystery, the value of cosmological critical density, the fine tuning issue, and expansion acceleration. A de Sitter Universe is predicted. The predicted time since last scattering is . This study gives motivation for scientific comparisons with experimental data.
To maintain the excellent performance achieved during Run 1 of the LHC, the Level-1 Trigger of the Compact Muon Solenoid (CMS) experiment underwent a significant upgrade. One part of this upgrade was the re-organization of the muon trigger path from a subsystem-centric view in which hits in the drift tubes (DT), the cathode strip chambers (CSC), and the resistive plate chambers (RPC) are treated separately in dedicated track-finding systems, to one in which complementary detector systems for a given region (barrel, overlap, and endcap) are merged at the track-finding level.
An overview of the new track-finder system for the barrel region, the Barrel Muon Track Finder (BMTF) as well as a comparison with the previous trigger are presented.
Icarus is the largest imaging LAr TPC ever operated. During its LNGS run on the CNGS neutrino beam, from 2010 to 2013, produced some thousands neutrino events of unprecedented quality. This was possible thanks its mechanical precision and stability, liquid argon purity and electronics front-end and DAQ. In this poster the last issue (front-end and DAQ) will be presented in detail. Actually Icarus T600, in view of its operation at FNAL on the SBN neutrino beam, is undergoing a major overhauling that implies cathode mechanics improvement, additional PMTs installation and a new electronics front-end and DAQ. This electronics implements a new architecture, integrated onto the flange proprietary design, and a new front-end that improves S/N and induction signals treatment. Also this issue will be presented in detail together with data recently recorder at CERN in the Icarino, 50 litres, LAr facility.
The laws of thermodynamics are fundamental laws of nature that classify energy changes for macroscopic systems as work performed by external driving and heat exchanged with the environment.The extension of thermodynamics to include quantum fluctuations faces unique challenges, such as the proper identification of heat and work, and the clarfication of the role of quantum coherence. We use a near-quantum-limited detector to experimentally track individual quantum trajectories of a driven qubit formed by the hybridization of a waveguide cavity and a transmon circuit. For each measured quantum coherent trajectory, we separately identify energy changes of the qubit as heat and work, and verify the first law of thermodynamics for an open quantum system. We further employ a novel quantum feedback loop to compensate for the exchanged heat and effectively isolate the qubit. By verifying the Jarzynski equality for the distribution of applied work, we demonstrate the validity of the second law of thermodynamics. Our results establish thermodynamics along individual quantum trajectories.
To make quantum theory consistent, models of spontaneous wave function collapse (collapse models) propose to modify the Schrödinger equation by including nonlinear and stochastic terms, which describe the collapse of the wave function in space. These spontaneous collapses are “rare” for microscopic systems, hence their quantum properties are left almost unaltered. At the same time, since these effects add coherently in composite systems, macroscopic spatial superpositions of macro-objects are rapidly suppressed. I will review the main features of collapse models, in a pedagogical way, by presenting the GRW (Ghirardi-Rimini-Weber) collapse model. Next, I will present an update of the most promising ways of testing them in interferometric and non-interferometric experiments, showing the current lower and upper bounds on their parameters.
TBA
We put forth a time-symmetric interpretation of quantum mechanics that does not stem from the wave properties of the particle. Rather, it posits corpuscular properties along with nonlocal properties, all of which are deterministic. This change of perspective points to deterministic properties in the Heisenberg picture as primitive instead of the wave function, which remains an ensemble property. This way, within a double-slit experiment, the particle goes only through one of the slits. In addition, a nonlocal property originating from the other distant slit has been affected through the Heisenberg equations of motion. Under the assumption of nonlocality, uncertainty turns out to be crucial to preserve causality. Hence, a (qualitative) uncertainty principle can be derived rather than assumed.
This talk will be partially based on:
Y. Aharonov, E. Cohen, F. Colombo, T. Landsberger, I. Sabadini, D.C. Struppa,J. Tollaksen, Finally making sense of the double-slit experiment, Proceedings of the National Academy of Sciences (2017) doi: 10.1073/pnas.1704649114
We discuss certain aspects of neutron-antineutron transition breaking conservation of baryon charge. In particular, we analyze discrete C, P, T symmetries and comparison between oscillations in vacuum and limitations from nuclei stability.
The interest of modern nuclear physics in weakly bound nuclei far from stability and in emergence of collective phenomena generates new attention to questions related to formation of mean field, pairing, other collective modes, and their interplay. The theoretical methods borrowed from macroscopic techniques turn out to be insufficient for finite systems such as nuclei. For example, weak pairing that inhibits Cooper phenomenon, particle number non-conservation, proximity of continuum states, strong coupling of collective modes, weak mean field, all suggest the need for these theories to be revised. In this presentation we tackle these problems; we take the path laid out by S.T. Belyaev and use equations of motion to couple the collectivities and to establish simple numerical procedures allowing for solutions with exact particle-number conservation. We use simple models and configuration interaction solutions to demonstrate the workings of proposed methods.
It is shown that low density nuclear matter is unstable with respect to alpha particle (quartet) formation. Since alpha particles are bosons, there occurs Bose-Einstein condensation (BEC). We calculate the critical temperature and solve the orderparameter equation at zero temperature. It is demonstrated that there exists a critical density at which quartet condensation disappears. Density, therefore, triggers a quantum phase transition (QPT). This does not happen for pairing where no QPT as a function of density exists. Rather there is a smooth transition from BEC to the BCS regime.
The fameous Hoyle 0^+ state at 7.65 MeV in 12C will be identified as a precursor of alpha particle condensation. Applying this scenario to the Hoyle state all known experimental facts of the Hoyle state are well reproduced without adjustable parameter. This is in particular true for the inelastic form factor. Other possible Hoyle-like states in heavier self-conjugate nuclei will be identified.
Since the famous article of 1959 by S.T. Belyaev [1], a crucial role of the first 2+ excitations in even-even nuclei, the quadrupole “phonons”, is one of conventional cornerstones of nuclear theory. The quadrupole phonons are the surface vibrations, belonging to the Goldstone branch related to the spontaneous breaking of the translation symmetry in nuclei. In the modern self-consistent nuclear theories based on the use of the effective energy density functionals (EDFs), a problem of accounting for effects of particle-phonon coupling (PC) effects looks rather delicate as they are included to the EDF phenomenological parameters on average. Hence, there is a problem of ”double counting”.
Within the self-consistent Theory of Finite Fermi Systems (TFFS), we developed a model for
consideration of the PC corrections to electromagnetic moments of odd spherical nuclei in which the fluctuating part of such corrections is taken into account only. The main idea of this model is to separate and explicitly consider such PC diagrams that behave in a non-regular way, depending significantly on the nucleus under consideration and the single-particle state of the odd nucleon. The rest (and the major part) of the PC corrections is supposed to be regular and included in the initial values of the TFFS parameters. In addition to the usual pole diagrams, so-called tadpole ones are included to the calculation scheme. The self-consistent scheme we use is based on the Fayans EDF [2].
In such approach, the quadruple phonos are most important, as their collectivity behaves in a
non-regular way, changing dramatically from double magic nuclei to non-magic neighbors. The model is developed for semi-magic nuclei, which contain a superfluid subsystem and a normal one, and besides the odd nucleon belongs to the normal subsystem. It simplifies the problem drastically. In addition, a non-regular behavior of the PC corrections is typical namely for the normal subsystem of a semi-magic nucleus. The model was used for finding PC corrections to the magnetic [3] and quadrupole [4] moments of the proton-odd neighbors of the even Pb and Sn isotopes. Among the PC terms, the ”end correction” and the induced interaction one are sufficiently bigger than all other. However, they have opposite signs and cancel each other significantly. Therefore, the self-consistency of the calculations is of primary importance. In the result, ”small corrections”, in particular the one due to the magnetic moment or quadrupole moment of the phonon, play also a role. In the last case, the tadpole diagram is of principal importance. In our calculations, rather good description of the data was obtained without any adjusted parameters.
Gamow shell model (GSM), the complex-energy continuum shell model in Berggren basis, can be equivalently formulated either in the basis of Slater determinants, or in the basis of reaction channels, providing the unified approach to nuclear structure and reactions. In the Sater determinant representation, GSM is a tool par excellence for nuclear structure studies of bound and unbound many-body states. In the second representation, GSM provides the microscopic theory of low energy reactions and many-body resonances. In the talk, I will present this unified theory of structure and reactions and give examples of recent applications.
The DAMA/LIBRA experiment is in data taking in the underground Gran Sasso Laboratory. The data collected by DAMA/LIBRA-phase1 have been released, and considering also the former DAMA/NaI experiment, the data of 14 independent annual cycles (total exposure 1.33 ton x yr) - analysed by exploiting the model-independent Dark Matter (DM) annual modulation signature - have given evidence at 9.3σ C.L. for the presence of DM particles in the galactic halo. No systematic or side reaction able to mimic the observed eect has been found or suggested by anyone. Other kinds of investigations have been recently performed and will be introduced here.
At present, after an upgrade of the experiment, DAMA/LIBRA is running in its phase-2 with increased sensitivity. R&D's towards a possible future phase-3 are in progress. Finally, the possibility of a low background pioneer experiment to exploit the directionality approach by using anisotropic ZnWO4 scintillators is discussed.
We will make the case that pedal coordinates (instead of polar or Cartesian coordinates) are more natural settings in which to study force problems of classical mechanics in the plane. We will show that the trajectory of a test particle under the influence of central and Lorentz-like forces can be translated into pedal coordinates at once without the need of solving any differential equation. This will allow us to generalize Newton theorem of revolving orbits to include nonlocal transforms of curves. Finally, we apply developed methods to solve the ``dark Kepler problem'', i.e. central force problem where in addition to the central body, gravitational influences of dark matter and dark energy are assumed.
The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) experiment located at Laboratori Nazionali del Gran Sasso in Italy searches for dark matter particles elastically scattering off nuclei. The target consists of scintillating CaWO4 crystals operated as cryogenic calorimeters at millikelvin temperature. Separate cryogenic light detectors observe the scintillation light produced in particle interactions to allow event-by-event particle identification for background suppression. CRESST-II phase 2, completed in 2015, puts the most stringent limits on elastic spin-independent dark matter-nucleon scattering for particle masses below 1.7 GeV/c². The CRESST-III experiment started taking data in August 2016 with a new generation of detector modules designed for unprecedented sensitivity to low-mass dark matter. The achieved detector performance and first results from CRESST-III will be presented.
Directional dark matter detection is next-generation experiment of dark matter search. By means of directional information, it can give a constraint on the velocity distribution of dark matter. Especially we investigate the possibility to measure anisotropy of the distribution with gaseous and solid detector in this work.
We study a model of keV-scale sterile neutrino with
relatively large mixing with the Standard Model sector. Usual
considerations predict active generation of such particles in the
Early Universe, which leads to constraints from the total Dark
Matter density and absence of X-ray signal from sterile neutrino
decay. These bounds together may deem any attempt of creation of
the keV scale sterile neutrino in the laboratory unfeasible. We
argue that for models with a hidden sector coupled to the sterile
neutrino these bounds can be evaded, opening new perspectives for
the experimental studies at neutrino facilities such as Troitsk $\nu$-mass and KATRINE. We estimate the generation of sterile neutrinos in
scenarios with the hidden sector dynamics keeping the sterile
neutrinos either massless or superheavy in the early Universe; in
both cases the generation by oscillations from active neutrinos in
plasma is suppressed.
After more than ten years of experimental and theoretical scrutiny, the now venerable $X(3872)$, $X(3915)$ and other neutral $XYZ$ states remain puzzling mysteries. It seems that the more we learn about them, the more they defy understanding. Basic properties of the $X(3872)$, including its natural width and whether its mass is above or below the ($m_{D^0} + m_{D^{*0}}$) threshold, are still not known. Likewise $X(3915)$ $J^{PC}$ determination, for its production in $B\to KX(3915)$; $X(3915)\to J/\psi\omega$ decays and in $\gamma\gamma\to J/\psi\omega$ collisions, as well as observations (or stringent limits) on decays to other final states, such as $\eta\eta_c$ and $D\bar{D}$, are needed. This talk will make some comments about strategies for distinguishing between different theoretical models and recommendations about possible directions for near-future research related to these particles.
In this talk we will present the experimental studies of the tetraquark candidate Zc states via its decays to charmonium states. The main results discussed are from the BESIII experiment, but results in other experiments will also be covered. We will show some model interpretations on these Z_c's and their potential connections to the Z_c states observed in decays to open charm mesons.
We will review the status and recent results on the charged
bottomonium-like states $Z_b(10610)$ and $Z_b(10650)$, produced in single pion
transitions from the $\Upsilon(5S)$ and $\Upsilon(6S)$. We will describe
their observation in the $\pi\Upsilon(nS)$ and $\pi h_b(nP)$ channels,
measurement of their spins and parities, and investigation of the open
flavor decays. Possible interpretations of the $Z_b$ states will also be
discussed.
Apart from the traditional vector charmonium states $\psi(3770), \psi(4040), \psi(4160)$, and $\psi(4415)$ above open charm, some experiments have observed a lot of non-traditional vector charmonium state which we call Y states, such as Y(4260) in $\pi^+\pi^- J/\psi (\pi^0\pi^0 J/\psi)$ line shape, Y(4360) and Y(4660) in $\pi^+pi^-\psi(3686)$ line shape. People also observed the non-traditional state Y(4140) via B decay.
Recently, BESIII Collaboration found that there are finer structures Y(4220) and Y(4320) in $e^+e^-\rightarrow\pi^+\pi^- J/\psi$ line shape around $\sqrt{s}=$ 4.26 GeV, Y(4220) and Y(4390) in $e^+e^-\rightarrow\pi+\pi^-h_c$ line shape around $\sqrt{s}=$ 4.30 GeV. BESIII Collaboration try to search the potential Y state in $e^+e^-\rightarrow\omega\chi_{cJ}$ line shape. However, no any exact conclusion is drawn with the current statistic. BESIII Collaboration also perform a search for Y(4140) via $e^+e^-\rightarrow \gamma\phi J/\psi$. However, no obvious signal is observed, either.
Multimode entanglement is an essential resource for quantum information processing. However, multimode entangled states are generally constructed by targeting a specific entanglement configuration. This yields to a fixed experimental setup that therefore exhibits reduced versatility and scalability. Here we demonstrate a reconfigurable highly multimode entangled state generated by parametric down conversion of a mode locked laser source. Without altering either the initial squeezing source or the experimental architecture, we realize the construction of many cluster states of various sizes and connectivities. More generally we show that this system enables the complete characterization of quantum correlations and fluctuations for any multimode Gaussian state. Progress in the direction of non-gaussian multimode states will be also reported.
Quantum information has traditionally employed qubits (quantum bits) to encode and process quantum information because of their obvious analogy to (classical) bits and the fact that digitisation allows for errors to be corrected, even at the quantum level. Nevertheless, continuous quantum variables afford distinct advantages in terms of producing extremely large-scale resource states (cluster states with over 1 million entangled modes) for quantum computing while using only minimal experimental equipment. In addition, this approach offers new tools for nonpertubative analysis of the behaviour of quantised detectors interacting with a relativistic quantum field. I will provide an overview of the latest theoretical and experimental advances at the forefront of continuous-variable quantum theory and technology for use in quantum computing and relativistic quantum information.
Relativistic Quantum Information is a novel area of research that aims at understanding the interplay of relativity and quantum physics, using tools from different fields of science, such as Gravity, Quantum Field Theory in Curved Spacetime, Quantum Information, Quantum Metrology and Quantum Thermodynamics.
Research in this area of science has provided novel insight on the role that paradigmatic quantum features, such as entanglement, have in physical processes that encompass relativistic and quantum features. Experiments aimed at testing these predictions, as well as developing novel technologies based on this body of work, are currently being developed.
Ultimately, scientists in this field believe that planned experiments might provide unexpected deviations from the theoretical predictions, an event that will stimulate novel theoretical directions.
We present recent advances in the field of Relativistic Quantum Information. We focus on a newly established line of research that aims at understanding the role of entanglement in the theory of gravitation. On the testable side, we discuss predicted effects of curved spacetime on lab-based experiments and space-based quantum information protocols. On the more challenging and exotic side, we propose the idea that not all energy gravitates. We motivate this idea an discuss applications and implications, and how this proposal promises to change our understanding of gravitation of quantum systems.
Vacuum fluctuations play a decisive role in many effects in quantum field theory and cosmology. When a parameter in the Lagrangian of the field is modulated by an external pump, vacuum fluctuations stimulate spontaneous downconversion processes, resulting in squeezing between modes symmetric with respect to half of the frequency of the pump. We have observed this phenomenon in the microwave domain, by using an array of SQUIDs with flux-bias tunable Josephson inductance, which creates a tunable speed of light along the array. We have extracted the full 4 × 4 covariance matrix of the emitted microwave radiation, demonstrating that photons at frequencies symmetrical with respect to half of the modulation frequency are entangled [PNAS 110, 4234 (2013)]. Next, we have shown that by double parametric pumping of a superconducting microwave cavity, it is possible to generate another type of correlation, namely coherence between photons in separate frequency modes [Nature Communications 7, 12548 (2016)]. The coherence correlations are controllable by the phases of the pumps and are established by a quantum fluctuation that stimulates the simultaneous creation of two photon pairs. We have shown that the origin of this vacuum-induced coherence is the absence of which-way information in the frequency space. In this contribution I will also discuss the prospects of utilizing superconducting circuits for realizing analog relativistic and cosmological effects.
We study the butterfly effect by considering shock wave solutions near the horizon
of the AdS black brane in some of 3-dimensional Gravity models including; 3D Einstein Gravity, Minimal Massive 3D Gravity, New Massive Gravity, Generalized Massive Gravity, Born-Infeld 3D Gravity and New Bi-Gravity. We calculate the butterfly velocities of these models and also we consider the critical points and different limits in some of these models. By studying the butterfly effect in the Generalized Massive Gravity, we observed a correspondence between the butterfly velocities and right-left moving degrees of freedom or the central charges of the dual 2D Conformal Field Theories.
Cosmic ray experiments with emulsion chambers exhibit several unusual phenomena which are hard to interpret within the Standard Model. We present the systematic survey of most intriguing exotic events such as coplanar or aligned events, penetrating hadrons with abnormally weak absorption in lead, ‘Centauro’-type events, gamma-hadron families with huge halos and some other types of events which are detected at energies and in kinematic regions beyond the reach of modern colliders including the LHC and RHIC. However, several new phenomena recently observed at colliders seem to be relevant to the cosmic ray unusual events. Possible theoretical approaches for explanation of exotic phenomena are discussed.
The width of $f_1 (1285) \to e^+e^-$ decay is calculated in the vector meson dominance model. The result depends on the relative phase between two coupling constants describing $f_1 \to \rho^0\gamma$ decay. The $\Gamma (f_1 \to e^+e^-)$ is estimated to be $\simeq 0.07 \div 0.19$ eV. Direct $f_1$ production in $e^+e^-$ collisions is discussed, and the $e^+e^- \to f_1\to a_0 \pi \to \eta \pi \pi$ cross section is calculated. Charge asymmetry in the $e^+e^- \to \eta \pi^+ \pi^-$ reaction due to interference between the $e^+e^- \to f_1$ and $e^+e^- \to \eta \rho^0$ amplitudes is studied.
Experimental results on top-quark physics obtained at the CMS experiment are reported based on the data recorded at centre-of-mass energy up to 13 TeV. Inclusive and differential cross sections for both top-quark pair and single top-quark production are presented, as well as measurements of top-quark properties in production and decay, and searches for anomalous couplings. The presented measurements test theoretical predictions, including recent perturbative QCD calculations, provide constraints of fundamental standard model parameters, and set limits on physics beyond the standard model.
To be submitted
Efforts by the United States Physics Departments to improve their Undergraduate Physics Programs and Curricula, and to increase the number of B.S. degrees awarded, as initiated by the American Physical Society, the American Institute of Physics and the American Association of Physics teachers will be presented. Recent efforts to modernize the undergraduate program and curriculum of the Physics Department of Kent State University in Ohio will be also presented. The revised program is based on a new curriculum, a new student advising structure and the creation of an environment of community and belonging for undergraduate physics students. The new curriculum aims at preparing students not only for entry into the graduate school but also for employment in the industrial and high-technology private sector.
The performance of CMS detector on early 2017 data will be presented. Especial attention will be given to the performance of the recently upgraded components, and in particular to the newly installed silicon pixel detector.
Recent developments of heavy ion accelerator facilities based on superconducting linacs and large synchrotron rings offer new capabilities for heavy ion nuclear physics.
Considerations are focused on new largest heavy ion drivers - mega-science projects NICA and FAIR being under construction – Nuclotron-based Ion Collider Facility in Dubna and the Facility for Antiproton and Ion Research in Darmstadt. Both will provide worldwide unique accelerator and experimental facilities allowing for a large variety of unprecedented fore-front research in beam physics, high energy density physics and applied science.
This presentation outlines recent achievements in high power linear accelerator injection chains, rapid cycling superconducting magnets of large synchrotron rings, ultra-high dynamic vacuum technologies, efficient accumulation and cooling of intense heavy ion beams.
Reference: http://nica.jinr.ru/
www.fair-center.eu
We will review the status and recent results on vector bottomonium-like
states above the $B\bar{B}$ threshold: the $\Upsilon(4S)$, $\Upsilon(5S)$
and $\Upsilon(6S)$. We will discuss their decays to both open and hidden flavor
channels and their line-shapes in various exclusive cross sections. The
properties of these states are at odds with the expectations for a pure
$b\bar{b}$ state, proposed explanations will be discussed.
Recent BESIII results on exotic hadron candidates, including both heavy charmonium-like states and light hadron exotics, will be reviewed, as well as introductions to the BEPCII collider and BEESIII detector. Future BESIII running plans, specially the physics program for the extotic hadron spectropy, will be discussed.
A scheme for parallel, high-throughput continuous-variable QKD (CV-QKD) is presented that efficiently utilizes the optical bandwidth resource of broadband squeezed vacuum (of order $10-100$THz), using a novel method for broadband spectrally resolved parametric homodyne measurement. Large multi-bit frames of data can be encoded simultaneously onto the squeezed vacuum spectrum by shaping its spectral phase using a Fourier-domain pulse shaper. This data can later be decoded at the receiving end by measuring the spectral quadrature fluctuation across the entire spectrum on a linear array of fast detectors using the pump field as a single local oscillator for all frequency pairs in the spectrum. The speed-up of the proposed protocol compared to standard protocols is proportional to the number of detectors in the array, which ideally can reach $10^5$ (defined by the ratio of the total bandwidth to the modulation rate of a single channel), and practically can be well over 100.
Our Scheme relies on a common version of CV-QKD, where the data is encoded onto the amplitude and phase of squeezed vacuum light (or the field quadratures) and is read out by coherent homodyne detection against a local oscillator [1]. CV-QKD is considered faster than discrete variable QKD because of the technical details of homodyne detection, which allow faster measurement than photon counting. In addition it may allow use of multiple photons per detection (and transfer multiple data bits per detection correspondingly) [2]. The security of the communication relies on the inability to measure both quadratures simultaneously, indicating that a receiving party can measure only one quadrature with no information on the other. Moreover, variation of the quadrature axis (phase of the pump) between (0,π⁄2) and (π⁄4,-π⁄4) naturally defines two mutually exclusive bases, where measurement along the (π⁄4,-π⁄4) axis cannot provide any information for a state that was squeezed along the other (0,π⁄2) axis, very similar to measuring the polarization of a single photon along the wrong axis of polarization.
References
Shallow water waves scattering on a draining and rotating flow constitute the analogue of a rotating black hole. In such a spacetime, it has been shown theoretically that, at low frequency, waves can extract angular momentum, hence energy from the black hole. Such a process is known as superradiance. In this talk, I will present the experiment conducted at the University of Nottingham that led to the first detection of superradiance in a vortex flow. In addition, I will give a geometric interpretation to one aspect of our result by extending the notion of geodesics to a dispersive system.
We develop a quantum scattering theory with the different wave packets: coherent states, Schroedinger cats, vortex beams with orbital angular momentum, Airy beams, etc. Examples from QED, QCD and potential scattering on atoms are treated. A phase-space picture of the quantum scattering (via the Wigner functions) is developed and a contribution of possible negativity of the incoming packets' Wigner functions to the cross-section is studied. The means of extracting a contribution of phases of the scattering amplitudes (of a Coulomb- and a hadronic one) in a collision experiment beyond the plane-wave approximation are discussed.
Outline of the talk is:
• QCD vacuum, QCD instanton vacuum [1].
• Instanton Liquid Model (ILM) vs Dyons Liquid Model (DLM) [2].
• Gluons in the ILM. Pobylitsa Eq. [3] for the gluon propagator in the ILM.
Dynamical gluon mass.
• Heavy quarks $Q$ in the ILM [4]. $Q\bar Q$-potential within the ILM.
• Heavy and light quarks in the ILM [5].
• Heavy quark light mesons interactions [6].
• Conclusion.
References
[1] D. Diakonov, Prog. Part. Nucl. Phys. 51(2003)173, arXiv:hep-ph/0212026;
T. Schäfer, E. Shuryak, Instantons in QCD, Rev.Mod.Phys. 70(1998)323, hep-ph/9610451;
[2] T.C. Kraan and P. van Baal, Phys. Lett. B428(1998)268, arXiv:hep-th/9802049; Nucl. Phys.
B533(1998)627, arXiv:hep-th/9805168; K. Lee and C. Lu, Phys. Rev. D58(1998)025011, arXiv:hep-th/9802108;
D. Diakonov, Nucl. Phys. Proc. Suppl. 195(2009)5, arXiv:0906.2456 [hep-ph];
Yizhuang Liu, E. Shuryak, I. Zahed, Phys.Rev. D92(2015)085006, arXiv:1503.03058 [hep-ph];
[3] P. V. Pobylitsa, Phys. Lett. B226(1989)387;
[4] U. Yakhshiev, Hyun-Chul Kim, B. Turimov, M.M. Musakhanov, Emiko Hiyama, Instanton effects on the heavy-quark static potential, Chinese Physics C (accepted for the publication), arXiv:1602.06074 [hep-ph];
[5] M. Musakhanov, Eur. Phys. J. C 9 (1999) 235; M. Musakhanov, Heavy-light quarks interactions in QCD vacuum, PoS BaldinISHEPPXXII (2015) 012, arXiv:1412.4472 [hep-ph];
[6] M. Musakhanov, Heavy-heavy and heavy-light quarks interactions generated by QCD vacuum,
EPJ Web Conf. 137 (2017) 03013, arXiv:1703.07825 [hep-ph].
KamLAND-Zen is the neutrinoless double beta decay experiment using 136Xe in the 1,000ton ultra pure liquid scintillator KamLAND. The observation of the neutrinoless double beta decay would help our understanding of neutrino mass and hierarchy by demonstrating the Majorana particle. KamLAND-Zen 400 was ended successfully in 2015. We measured the 136Xe double beta decay life time precisely, and got the limit of neutrinoless double beta decay life time. KamLAND-Zen 800 is a improved experiment using 800kg of 136Xe. This experiment have a potential to survey in inverted hierarchy region of the neutrino mass. I will report KamLAND-Zen 800 status and future prospect.
The 760 ton liquid argon ICARUS T600 detector performed a successful three-year physics run at the underground LNGS laboratories, studying neutrino oscillations with the CNGS neutrino beam from CERN, and searching for atmospheric neutrino interactions in cosmic rays. A sensitive search for LSND like anomalous nu_e appearance was performed, contributing to constrain the allowed parameters to a narrow region around Δm$^2$~eV$^2$, where all the experimental results can be coherently accommodated at 90% C.L.
The T600 detector will be redeployed at Fermilab, after a significant overhauling, to be exposed to the Booster Neutrino Beam acting as the far station to search for sterile neutrino within the SBN program.
The proposed contribution will address ICARUS LNGS achievements and the ongoing analyses also finalized to the next physics run at Fermilab.
"The European Researchers' Night: concepts and impact" -
Dr George Fanourakis -
Institute of Nuclear and Particle Physics, NCSR "Demokritos", Greece
Abstract: The European Researchers' Nights is a European instrument to allow the general public, whichever their age and background, to meet researchers and consequently get informed about the importance and the benefits of Scientific Research as well as to motivate young people to follow Scientific Research carriers. It is defined as the last Friday of every September, it runs at University, Research Center Campuses and other well established public places and it deploys many innovative and imaginative methodologies to invite the public of all ages to attend and enjoy the event. This year is the 12th year of the European Researchers' Night event and as usual it will take place in more than 300 cities in Europe. In this presentation, we will discuss the concepts of this renowned Night in Europe and we will present our experience of RENA, a Greek consortium of Research and Educational establishments, with the activities and measured impact of the European Researchers' Night.
This talk describes a small-scale piece of research using concept mapping to elicit A Level students’ understandings of particle physics, a paper about which was published in Physics Education (52). Fifty-nine Year 12 (16- and 17-year-old) students from two London schools participated. The exercise took place during school physics lessons. Students were instructed how to make a concept map and were provided with 24 topic-specific key words. Students’ concept maps were analysed by identifying the knowledge propositions they represented, enumerating how many students had made each one, and by identifying errors and potential misconceptions, referring to the examination specification they were studying. The only correct statement made by most of the students in both schools was that annihilation takes place when matter and antimatter collide, although there was evidence that some students were unable to distinguish between annihilation and pair production. A high proportion of students knew of up, down and strange quarks, and that the electron is a lepton. However, some students appeared to have a misconception that everything is made of quarks. Students found it harder to classify tau particles than they did electrons and muons. Where students made incorrect links about muons and tau particles their concept maps suggested that they thought they were mesons or quarks.
The Hellenic Open University Cosmic Ray Telescope consists of three autonomous stations installed at the University Campus in the city of Patras in western Greece. Each station comprises three large (1 square meter) plastic scintillators and a Codalema type RF antenna detecting Extensive Air Showers originating from primary particles with an energy threshold of 10 TeV. The construction of the charge particle detectors, the calibration procedures, the experimental methods as well as the operation and the performance of the Telescope are presented, demonstrating also its educational utilization in the framework of the HEllenic LYceum Cosmic Observatories Network (HELYCON).
The “open online education” paradigm is challenging the future role of Universities, open or conventional, as well as that of their faculty members. Some say that large traditional universities will have the fate of the dinosaurs, unless they adapt quickly to the new environment. This issue has been at the heart of a debate among faculty, administrators and students in Greek universities, since the launching in 2013 of the “Opening up Greek Universities” initiative, an ambitious project aiming at opening up approximately 3,900 courses selected from the undergraduate and graduate curricula of 26 Greek universities. The developed open courses have been made freely available to the general public through a national portal. The project results are presented, including the specifications of the online courses, and the support services and technological infrastructure. Also, views and policies regarding the development of open educational material and courses, and the new opportunities and risks are also discussed.
Driven by the availability of modern photolithographic techniques, Micro Pattern Gas Detectors (MPGD) have been introduced at the end of the 20th century by pioneer developments: Microstrip Gas Chambers (MSGC), Gas Electron Multipliers (GEM) and Micromegas, later followed by thick-GEM (THGEM), resistive GEM (RETGEM) and other novel micro-pattern devices. Nowadays intensive R&D activities in the field of MPGDs and their diversified applications are pursued by the large CERN- RD51 collaboration. The aims are to facilitate the development of advanced gas-avalanche detector concepts and technologies and associated electronic-readout systems, for applications in basic and applied research. MPGD systems now offer robustness, very high rate operation, high precision spatial resolution (sub 100-micron), and protection against discharges. MPGDs became important instruments in current particle-physics experiments and are in development and design stages for future ones. They are significant components of the upgrade plans for ATLAS, CMS, and ALICE at the LHC, exemplifying the beneficial transfer of detector technologies to industry. Beyond their design for experiments at future facilities (e.g. ILC), MPGDs are considered for rare-event searches, e.g. dark matter, double beta decay and neutrino scattering experiments. Detectors sensitive to x-rays, neutrons and light are finding applications in other diverse areas such as material sciences, hadron therapy systems, homeland security etc. The areas of research activities within the RD51 MPGD collaboration includes detector physics & technology, model simulations, readout electronics, production techniques, common test facilities, and applications. By this broad coverage RD51 brings together leading experts in the field of detector science and detectors users, resulting in effective progress over a wide array of applications. This talk will review the activities of the RD51, its major accomplishments so far, and future plans.
The Electron Ion Collider (EIC) is the project for a new US-based, high-energy, high-luminosity facility, capable of a versatile range of beam energies, polarizations, and ion species. Its primary goal is to precisely image quarks and gluons and their interactions inside hadrons, in order to investigate their confined dynamics and elucidate how visible matter is made at its most fundamental level. I will describe the current status of the project and briefly touch upon the main physics questions addressed by such a facility. If time allows, I will give few more details on the topic of Transverse Momentum Dependent parton distributions (TMDs).
A number of charged and neutral candidates for exotic mesons with hidden charm were observed in amplitude analyses of B meson decays, explaining the peaking structures in $J/\psi\pi^{\pm}$, $\chi_{c1}\pi^{\pm}$, $\psi(2S)\pi^{\pm}$ and $J/\psi\phi$ mass distributions. We review the experimental information on these candidates and discuss their possible interpretations.
all LHCb measurements related to pentaquark candidates will are presented. Possible interpretations of the Pc(4450) and Pc(4380) states will be discussed.
We discuss the question of how many Unruh particles can be found in a finite volume.
There exist various conditions under which waves of positive and negative Klein-Gordon norm can be made to convert into each other.
For example, upon propagating on a curved background, waves of positive and negative norm mix to generate outgoing waves.
As a result of this scattering process, field quanta are spontaneously emitted from the vacuum --- the most famous instance of this effect undoubtedly is the mixing of positive and negative norm waves at the horizon of black holes, which results in a steady thermal flux to be emitted from the hole, Hawking radiation [1].
The event horizon of the black hole is the point at which the curvature of spacetime is such that the escape velocity out to infinity becomes superluminal, thus restricting wave propagation to one direction only: toward the central singularity.
Wave propagation on a curved background geometry is not restricted to astrophysics: it is possible to realise an effectively curved geometry with moving wave media in the laboratory, and, in particular, the kinematics of waves at the horizon [2].
An artificial event horizon can be created when a refractive index front (RIF) is moving at the speed of light in a dispersive optical medium [3].
The RIF could be created by a pulse of light that modifies the refractive index by the optical Kerr effect --- a nonlinear effect by which the refractive index depends upon the square of the electric field in the medium.
Light under the pulse will be slowed and thus the front of the pulse exhibits --- for some frequencies --- a black-hole type horizon capturing light. The back of the pulse acts as an impenetrable barrier, a white-hole horizon.
Both event horizons separate two discrete regions: under the pulse, where light is slow and the pulse moves superluminally and outside the pulse, where the pulse speed is subluminal.
We reveal the properties of spontaneous emission from the vacuum at a moving refractive index step in a dispersive dielectric by expanding on an analytical model for light-matter interaction [4]. We establish the conditions for event horizons as a function of the speed and height of the step in the medium, and study the various configurations of modes of the field in the vicinity of the step with and without analogue horizons. We then analytically calculate the emission spectra from all modes of positive and negative norm in the laboratory frame [5]. We find that, as a result of the various mode configurations, the spectrum is highly structured into intervals with black hole-, white hole-, and no horizon.
The emission spectrum in the laboratory frame is found to be a combination of emissions corresponding to different frequencies in the frame moving with the pulse, leading to a characteristic shape. In particular, the existence of a peak in the ultraviolet, associated with emission into a mode with negative norm, is an interesting feature of our spectrum.
We show how emission in this peak may be stimulated by scattering a coherent wave at the horizon.
We also report on an experiment to study the dynamics of waves at the optical horizon.
A weak CW-probe is made to scatter on a RIF created by an intense, ultrashort pulse in a photonic crystal fibre under fine-tuned horizon-like conditions.
As a result of mode conversion at the horizon, light at different wavelengths is generated: the probe is partially shifted in frequency --- positive-to-positive norm conversion occurs as predicted by our theory.
Furthermore, we investigate the companion effect of stimulated emission in a negative norm wave.
The effect of mode conversion is clearly shown to be a feature of horizon physics.
This experiment is a stimulated version of the spontaneous quantum effect at the heart of Hawking radiation.
[1] S. Hawking, Nature 248, 30 (1974).
[2] W.G. Unruh, Phys. Rev. Let. 46 (1981).
[3] T.G. Philbin et al Science 319, 1367 (2008).
[4] S. Finazzi and I. Carusotto, Phys. Rev. A 87, 023803 (2013).
[5] M. Jacquet and F. Koenig, Phys. Rev. A 92, 023851 (2015).
The unitary itself is usually described by an external observer that manipulates an interaction. Including this control into a fully quantum description, a so-called “quantum clock”, is thus a critical step to placing quantum protocols on a firm footing as well as understanding the fundamental limitations of quantum clocks; especially since due to information gain-disturbance principles, it is impossible to perform these operations perfectly. Here we present a quantum clock that performs a general energy-preserving unitary autonomously with an error that is exponentially small in both the dimension and the energy of the quantum clock.
The full quantum setup, —system to be controlled plus quantum clock— is described by a time independent Hamiltonian. This is crucial if one desires to understand the full quantum limitations to control, since a time dependent Hamiltonian would require external control, not explicitly accounted for. The main result is to show that this setup with a clock initially in a Gaussian superposition state can implement to any desired precision, any energy preserving unitary on the system during an arbitrarily small time interval with a back-reaction on the clock which is exponentially small in both energy and clock dimension. How fast as a function of energy and dimension the error in the back-reaction approaches zero is of paramount importance for understanding quantum resource theories involving time and control, since if the decay in error is too slow, one would have to invest a lot of work in correcting the error, representing an unaccounted-for cost to quantum thermodynamic resource theories.
Previous to this work, it was only known that unitaries can be implemented perfectly in the infinite energy and dimension limit, from which it is impossible to estimate the true cost of control. The model we present for the quantum clock is based on a model introduced by Eugene Wigner in General Relativity and later investigated in the non-relativistic regime by Asher Peres. Crucially, we consider a quantum superposition of so-called “clock states”, in contrast to Asher’s study. This is a crucial difference, which due to quantum constructive and destructive interference, leads to a much more accurate clock which can achieve the exponentially small error.
Our contributions to the field of quantum clocks also has other applications. For example, rather than using the quantum clock to perform timed unitaries on quantum systems, one can also perform weak measurements on the clock to measure time. Preliminary results suggest that our clock outperforms classical clocks governed by stochastic dynamics and the quantum clocks in Asher Pere’s study.
In conclusion, our work has implications for the fundamental limitations to the precision of quantum clocks and other applications such as timed autonomous control via these quantum devices. Our work is also both a benchmark for future implementations, as well as introducing a conjecture on the fundamental limitations of clocks and control.
Pre-print available on Arxiv: 1607.04591
To utilize a scalable quantum network and perform a quantum state transfer within distant arbitrary nodes, the coherence and control of the dynamics of couplings between the information units must be achieved as a prerequisite ingredient for quantum information processing within a hierarchical structure. Graph-theoretic approach provides a powerful tool for the characterization of quantum networks with nontrivial clustering properties. By encoding the topological features of the underlying quantum graphs, relations between the quantum complexity measures are presented revealing the intricate links between a quantum and a classical networks dynamics.
We study azimuthal angular correlations among final state particles produced in high energy processes in QCD and show that these correlations are a sensitive probe of dynamics of QCD at small x.
N. Korolkova, University of St. Andrews, UK; D. Mogilevtsev, Istitute of Physics, Belarus Academy of Sciences,Belarus; S. Mukherjee, R. R. Thomson, Heriott-Watt University, UK.
The engineering of dissipation to a common reservoir generates a vast array of novel structures for photonic application and quantum simulation [1]. We suggest here novel possibilities for photonics that are generated by diffusive light propagation [2]. The dissipative coupling of bosonic modes can allow light to flow like heat, whilst retaining coherence and even entanglement. The Photonic Circuit has generally been a structure in which light propagates by unitary exchange and where photons transfer reversibly between channels. In contrast, the term ‘diffusive’ is more akin to a chaotic propagation in scattering media, where light is driven out of coherence towards a thermal mixture. We have devised a way to unite these opposites, founded from the dynamics of open quantum systems and resulting in novel techniques for coherent light control. The crucial feature of these photonic structures is dissipative coupling between modes; an interaction with a common reservoir. We demonstrate experimentally that such systems can perform optical equalisation to smooth multimode light, or act as a distributor, guiding it into selected channels. Quantum thermodynamically, these systems can act as catalytic coherent reservoirs by performing perfect non-Landauer erasure. When extending to lattice structures, localized stationary states can be supported in the continuum, similar to compacton-like states in conventional flat band lattices. In the future, we believe that diffusive photonic systems will find practical application both in studying the fundamental processes of structurally engineered open systems and in an array of integrated photonic technologies.
[1] G. M. Palma, K-A. Suominen, and A. K. Ekert: Quantum Computers and Dissipation, Proc. Roy. Soc. London Ser. A 452, 567 (1996).
[2] S. Mukherjee, D. Mogilevtsev, G. Ya. Slepyan, T. H. Doherty, R. R. Thomson, N. Korolkova: Coherent Diffusive Photonics, arXiv:1703.06025 [quant-ph] (2017).
Particle physics addresses Gauguin’s fundamental questions about the Universe, its past and future, and our place within it.
I will present some recent works of ours examining the topic of quantum nonlocality from various perspectives. Weak measurements and weak values will be shown to have a significant role in most of these works. Upcoming experiments will be discussed as well.
Abstract: Quantum experiments are reaching relativistic regimes. Quantum communication protocols have been demonstrated between Earth and Satellite-based links. At these regimes the Global Positioning System requieres relativistic corrections. Therefore, it is necessary to understand how does motion and gravity will affect long-range quantum experiments. Interestingly, relativistic effects can also be observed at small lengths scales. Some effects have been demonstrated in superconducting circuits involving boundary conditions moving at relativistic speeds and quantum clocks have been used to measure time dilation in table-top experiments. In this talk I will present a formalism for the study of gravitational effects on quantum technologies. This formalism is also applicable in the development of new quantum technologies that can be used to deepen our understanding of physics in the overlap of quantum theory and relativity. Examples include accelerometers, gravitational wave detectors and spacetime probes underpinned by quantum field theory in curved spacetime.
Quantum simulators promise to give rise to new insights into dynamical and static properties of complex quantum systems, beyond what is available on classical supercomputers. There is already some good evidence that quantum simulators have the potential to outperform classical computers. Yet, in order to be prone against arguments claiming a lack of imagination, this superior computational capabilities should be expressed in terms of notions of computational complexity. One of the main milestones in quantum information science is hence to realize quantum devices that exhibit an exponential computational advantage over classical ones without being universal quantum computers in complexity theoretic terms, a state of affairs dubbed exponential quantum computational advantage or simply "quantum computational supremacy". The paradigmatic boson samplers are devices of this type. We end the talk by discussing a number of surprisingly simple and physically plausible schemes that once realized show such a quantum computational supremacy. Both aspects of physical implementation are discussed as well as mathematical arguments used in proofs relating to notions of computational complexity. We will see that while there is good evidence that these devices outperform classical computers, they can still be efficiently and rigorously certified in their trustworthy functioning.
Highlights from recent new physics searches with the ATLAS detector at the CERN LHC will be presented. They include searches for extra-dimension models, compositeness, new gauge bosons, leptoquarks, supersymmetry, among others. Results are based on analysis of pp collision data recorded at a centre-of-mass energy of 13 TeV.
An overview of the results of the experimental searches for exotica at the CMS experiment with 13 TeV collision data is presented. The results cover various models with different topologies such as searches for new heavy resonances, extra space dimensions, black holes and leptoquarks.
Summary of the workshop
We give a consistent quantum description of time, based on
Page and Wootters' conditional probabilities mechanism, that overcomes
the criticisms that were raised against similar previous proposals. In
particular we show how the model allows to reproduce the correct
statistics of sequential measurements performed on a system at
different times. I also hint at the possible ways one can extend the
argument to include space, and trace a roadmap towards a possible
quantum description of spacetime.
There are several fundamental predictions of quantum field theory, such as the
Sauter-Schwinger effect (electron-positron pair creation out of the vacuum
due to a strong electric field) or Hawking radiation (black hole evaporation),
which have so far eluded a direct experimental verification.
After a brief introduction into the basics of these effects, this talk will be
devoted to a discussion of the prospects for experimental studies, either
directly or by means of suitable laboratory analogues.
TBA
We develop a moment QCD sum rule method augmented by fundamental inequalities to study the existence of exotic doubly hidden-charm/bottom $QQ\bar Q\bar Q$ tetraquark states made of four heavy quarks. Using the compact diquark-antidiquark configuration, we calculate the mass spectra of these tetraquark states. There are 18 hidden-charm $cc\bar c\bar c$ tetraquark currents with $J^{PC} = 0^{++}$, $0^{-+}$, $0^{--}$, $1^{++}$, $1^{+-}$, $1^{-+}$, $1^{--}$, and $2^{++}$. We use them to perform QCD sum rule analyses, and the obtained masses are all higher than the spontaneous dissociation thresholds of two charmonium mesons, which are thus their dominant decay modes. The masses of the corresponding hidden-bottom $bb\bar b\bar b$ tetraquarks are all below or very close to the thresholds of the $\Upsilon(1S)\Upsilon(1S)$ and $\eta_b(1S)\eta_b(1S)$, except one current of $J^{PC}=0^{++}$. Hence, we suggest to search for the doubly hidden-charm states in the $J/\psi J/\psi$ and $\eta_c(1S)\eta_c(1S)$ channels.
Study of the charmonium states play important role in understanding of the strong interaction. The most interesting charmonium states lie near or above open charm thresholds. Nature of such states is of interest to modern physics. Recent lattice calculations have performed the necessary extrapolations and considered spectra as well as certain radiative transitions. The lattice QCD simulations of $X(3872)$ with $J^{PC} = 1^{++}$ have been performed in this study. The mass of this state , $3872$ MeV, is very close to the sum of the masses of the $D^0$ and $\overline{D^{0*}}$ mesons and decays to $D^0$ and $\overline{D^{0*}}$ were observed, giving rise to two other explanations for what the mysterious X could be: a loosely-bound “molecule” of the $D^0$ and $\overline{D^{0*}}$ mesons, or a “tetra-quark” binding a di-quark and a di-antiquark. We also have proposed the approach to determine the nature of this state.
We developed a Friedrichs-model-like scheme in studying the hadron
resonance phenomenology and present that the hadron resonances might
be regarded as the Gamow states produced by a Hamiltonian in which
the bare discrete state is described by the result of usual quark
potential model and the interaction part is described
by the quark pair creation model. In an almost parameter-free
calculation, the $X(3862)$, $X(3872)$, and $X(3930)$ state could be
simultaneously produced with a quite good accuracy by coupling the
three P-wave states, $\chi_{c2}(2P)$, $\chi_{c1}(2P)$, $\chi_{c0}(2P)$
predicted in the Godfrey-Isgur model to the $D\bar D$, $D\bar D^{*}$, $D^*\bar D^*$
continuum states. At the same time, we predict that the $h_c(2P)$
state is at about 3890 MeV with a width of about 44 MeV. In this
calculation, the $X(3872)$ state has a large compositeness. This scheme
may shed more light on the long-standing problem about the general
discrepancy between the prediction of the quark model and the observed
values, and it may also provide reference for future search for the
hadron resonance state.
The Abelian decomposition of QCD which decomposes
the gluons to the color neutral binding gluons
(the neurons and the monopoles) and the colored
valence gluons (the chromons) gauge independently
naturally generalizes the quark model to the quark
and chromon model which can play the central role
in hadron spectroscopy. We discuss how the quark
and chromon model describes the glueballs and
the glueball-quarkonium mixing in QCD. We present
the numerical analysis of glueball-quarkonium mixing
in $0^{++}$, $2^{++}$, and $0^{-+}$ sectors below
2 GeV, and show that in the $0^{++}$ sector $f_0(500)$
and $f_0(1500)$, in the $2^{++}$ sector $f_2(1950)$,
and in the $0^{-+}$ sector $\eta(1405)$ and $\eta(1475)$
could be identified as predominantly the glueball states.
We discuss the physical implications of our result.
In the talk, I examine the issues of the amplitude analysis related to the exotic states.
A building of the cascade decay amplitude becomes a non-trivial problem especially in the presence of the spin of particles in the final state.
We compare the helicity amplitudes and the amplitudes in the tensor formalism considering singularities and the crossing properties.
An interpretation of results of the partial wave analysis is often ambiguous. A picture of the sequential two-body decays is spoiled by the rescattering processes.
I will demonstrate an example of $a_1(1420)$ phenomenon observed in the $J^{PC} = 1^{++}\,f_0\pi\,P$-wave by COMPASS experiment.
I will also discuss the $Z_c(3900)$ exotic candidate as an application the advanced amplitude analysis to the heavy meson sector.
The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at neutron star core densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure rare diagnostic probes such as hadrons including multi-strange (anti-) hyperons, lepton pairs, and charmed particles with unprecedented precision and statistics. Most of these particles will be studied for the first time in the FAIR energy range. In order to achieve the required precision, the measurements will be performed at very high reaction rates of 1 to 10 MHz. This requires very fast and radiation-hard detectors, a novel data read-out and analysis concept based on free streaming front-end electronics, and a high-performance computing cluster for online event selection. The status of FAIR and the physics program of the proposed CBM experiment will be discussed.
The project NICA (Nuclotron-based Ion Collider fAcility) is under realization at the Joint Institute for Nuclear Research. The main goals are to study hot and dense baryonic matter at the extreme conditions and to investigate nucleon spin structure. The plan of NICA accelerator block development include an upgrade of existing superconducting (SC) synchrotron Nuclotron, construction of new injection complex, SC Booster, and SC Collider with two interaction points (IP). The collider will provide heavy ion collisions in the energy range up to 11.0 A GeV (for gold) and uo to 27 GeV (for polarized protons). The heavy ion collision program will be performed with the fixed target experiment Baryonic Matter at Nuclotron (BM@N) in the beam extracted from the Nuclotron, and with Multi Purpose Detector (MPD) at the first IP of NICA Collider. Investigation of nucleon spin structure and polarization phenomena is foresees with Spin Physics Detector (SPC) at the second IP of the Collider.
Entanglement in quantum mechanics contradicts local realism, and is a manifestation of quantum non-locality. Its presence can be detected through the violation of Bell, or CHSH inequalities.Paradigmatic quantum systems provide examples of both, non-entangled and entangled states.
Here we consider entanglement of non-local degrees of freedom emerging from topological properties of many-body systems. Specifically, we consider a minimal complexity setup consisting of 6 Majorana bound states. We find that any allowed state in the degenerate Majorana space is non-locally entangled. We show how to measure (with available techniques) the CHSH-violating correlations, using either intermediate strength or weak measurement protocols.
The discrete time quantum walk defined as a quantum-mechanical analogue of the discrete time random walk have recently been attracted from various and interdisciplinary fields. The weak limit theorem, that is,
the asymptotic behavior, of the one-dimensional discrete time quantum walk is analytically shown. From the limit distribution of the discrete time quantum walk, the discrete time quantum walk can be taken as the quantum dynamical simulator of some physical systems. In this talk, we would like to discuss the mathematical structures of the discrete time quantum walk and its experimental implementation.
To be submitted
The non-perturbative nature of the strong interaction leads to spectacular phenomena, such as the formation of hadronic matter, color confinement, and the generation of the mass of visible matter. To get deeper insight into the underlying mechanisms remains one of the most challenging tasks within the field of subatomic physics.The antiProton ANnihilations at DArmstadt (PANDA) collaboration has the ambition to address key questions in this field by exploiting a cooled beam of antiprotons at the High Energy Storage Ring (HESR) at the future Facility for Antiproton and Ion Research (FAIR) combined with a state-of-the-art and versatile detector. This contribution will address some of the unique features of PANDA that give rise to a promising and long-term physics program together with state-of-the-art technological developments.
Between November $1974$, when the $J/\psi$ particle was discovered, and $2003$,
when the $X(3872)$ resonance was hunted by the Belle Collaboration, the
charmonium spectrum was fairly explained by naive quark models. However, the
exploration of the spectrum for energies above the $D\bar{D}$ threshold has led
to the appearance of unexpected states, difficult to accommodate in the naive
quark model picture.
The mentioned $X(3872)$ has properties that cannot be explained assuming a
simple quark-antiquark structure; for example, its decay into $\pi\pi J/\psi$
through a $\rho$ meson is an isospin violating decay. However, this property can
be nicely explained in a picture in which the $X(3872)$ is understood as a
$D\bar D^{\ast}$ bound state, due to the isospin violation in the $D$ and
$D^{\ast}$ masses and the close position of the state to the $D^0\bar D^{*\,0}$
threshold. In addition to the $X(3872)$, there are other states such as the
$D_{s0}(2317)^\ast$ and $D_{s1}(2460)$ which can be described as a $DK$ and
$D^\ast K$ molecules, respectively; or the $P^\ast_c(4380)$ and
$P^\ast_c(4450)$ which are two exotic structures discovered in $2015$ by the
LHCb Collaboration in the $J/\psi p$ channel, lie near the $\bar
D\Sigma^{(\ast)}_c$ thresholds and are compatible with pentaquark
interpretations.
The common feature among all these exotic states is the presence of nearby
two-particle thresholds. This reinforces the intuition that the residual
interaction between the two particles can form a new molecular state or
renormalize the mass of the original naive $q\bar q$ state. Some times the
interaction is not enough to bind a molecule and a threshold cusp may be formed.
Then, one can expect that near each meson-meson or baryon-meson thresholds some
new structures might appear. The description of this type of structures is very
tricky from a theoretical point of view because the strength of the residual
interaction is usually model dependent and one can generate spurious states if
this interaction is not under control.
In this talk, we review the status of a threshold effects calculation in the
meson an baryon spectrum using a constituent quark model~[1], that has been
applied to a wide range of hadronic observables and thus all model parameters
are completely constrained. In the meson sector, the model has been able, for
instance, to reproduce the properties of the $X(3872)$ as a mixture of $c\bar c$
and $D\bar D^\ast$ channels~[2]; and to describe well the spectrum of the
$P$-wave charm strange mesons when $DK$ and $DK^\ast$ structures are taken into
account~[3]. In the baryon sector, the model has described the
$\Lambda_c(2940)^+$~[4, 5] as a $D^\ast N$ molecule, the $X_c(3250)$~[6] as
a $D^\ast\Delta$ one, and the $P^\ast_c(4380)$ and $P^\ast_c(4450)$ states as
$\bar D \Sigma^\ast_c$ and $\bar D\Sigma_c$ candidates~[7]. Some new states
which cannot be accommodated as molecular states will be also discussed.
\vspace{1cm}
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\hspace*{1.00cm} J. Segovia, A.M. Yasser, D.R. Entem, and F. Fern\'andez, Phys.
Rev. D78, 114033 (2008).
[2] P.G. Ortega, D.R. Entem and F. Fern\'andez, J. Phys. G40, 065107 (2013).
[3] P.G. Ortega, J. Segovia, D.R. Entem and F. Fern\'andez, Phys. Rev. D94,
074037 (2016).
[4] P.G. Ortega, D.R. Entem, F. Fern\'andez, Phys. Rev. D90, 114013 (2014).
[5] P.G. Ortega, D.R. Entem, F. Fern\'andez, Phys. Lett. B718, 1381-1384 (2013).
[6] P.G. Ortega, D.R. Entem, F. Fern\'andez, Phys. Lett. B729, 24-26 (2014).
[7] P.G. Ortega, D.R. Entem and F. Fern\'andez, Phys. Lett. B764, 207 (2017).
We show, on the basis of an analysis of four-point correlation
functions of quark bilinear currents in different channels and
the properties of leading and subleading QCD diagrams in the
large-$N_c$ limit, that if tetraquarks exist, then they generally
contribute at $N_c$-subleading orders of connected amplitudes.
This implies that, irrespective of their flavor content, tetraquarks
should have narrow widths, of the order of $N_c^{-2}$, i.e., an order
of magnitude smaller in $N_c$ than the widths of ordinary mesons.
Our results agree with those found earlier by Cohen and Lebed.
After the discovery of the Higgs boson, the measurement of its coupling properties are of particular importance. In this talk measurement of the cross sections and couplings of the Higgs boson in bosonic decay channels with the ATLAS detector are presented.
K->pinunu is one of the theoretically cleanest meson decay where to look for indirect effects of new physics complementary to LHC searches. The NA62 experiment at CERN SPS is designed to measure the branching ratio of the K+->pi+nunu decay with 10% precision. NA62 took data in 2015 and 2016 reaching the Standard Model sensitivity. The status of the experiments will be reviewed, and prospects will be presented.
The NA48 at CERN has recently published a limit on the presence of heavy neutrinos from decays of charged kaons into a pion and muons. The following NA62 experiment at CERN collected a large sample of charged kaon decays in flight with a minimum bias trigger in 2007. Upper limits on the rate of the charged kaon decay into a muon and a heavy neutral lepton (HNL) obtained from this data are reported for a range of HNL masses. The NA62 experiment has collected further data in 2015 with a completely new and improved detector. New limits on heavy neutrinos from kaon decays into pion, electron and positron will be presented.
The reconstruction and calibration of jets in ATLAS is a critical component in producing precise analyses, whether precision measurements or searches for new physics. This talk describes the steps involved in deriving the jet energy scale (JES) and presents the results. Calibrations and their uncertainties are shown using the full 2015 + 2016 datasets. The study of jet substructure has also become increasingly more prevalent throughout a wide array of searches and measurements. We also report on the latest results from ATLAS for the reconstruction and tagging of large-R jets as well as the calibration and determination of the uncertainties associated with these techniques.
((W Mass - STDM-2014-18, Z3D (W/Z precision 7 TeV - STDM-2012-20, W+jets 8 TeV - STDM-2016-14 , Z+1jet 8TeV - STDM-2016-11, kt splitting scales - STDM-2015-14, Z+jets 13TeV STDM-2016-01)
The electroweak sector of the Standard model can be tested by precision measurements of its fundamental parameters, such as the W boson mass or the electroweak mixing angle. In this talk, we present the first measurement of the W boson mass, based on the 7 TeV data set corresponding to an integrated luminosity of 4.6 fb-1. With these samples the detector and physics modelling has been studied in great detail, leading to an overall uncertainty of 19 MeV. The ATLAS collaboration also performed a new precise triple differential cross-section measurement as a function of M(ll), dilepton rapidity and cos?* defined in the Collins-Soper frame. This measurement provides sensitivity to the PDFs and the Z forward-backward asymmetry, AFB, which is derived and will be presented. This builds the foundation for a possible future extraction of the weak-mixing angle.
The production of jets in association with vector bosons is an important process to study perturbative QCD in a multi-scale environment. The ATLAS collaboration has performed new measurements of vector boson + jets cross sections, differential in several kinematic variables, in proton-proton collision data taken at center-of-mass energies of 8 TeV and 13 TeV, which will be presented. The measurements are compared to state-of-the art theory predictions. They are sensitive to higher-order pQCD effects, probe flavour and mass schemes and can be used to constrain the proton structure. In addition, we present a new measurement of the splitting scales of the kt jet-clustering algorithm for final states containing a Z-boson candidate at a centre-of-mass energy of 8 TeV.
The ATLAS experiment aims at recording about 1 kHz of physics collisions, starting with an LHC design bunch crossing rate of 40 MHz. To reduce the massive background rate while maintaining a high selection efficiency for rare physics events (such as beyond the Standard Model physics), a two-level trigger system is used. Events are selected based on physics signatures such as presence of energetic leptons, photons, jets or large missing energy. The trigger system exploits topological information, as well as multi-variate methods to carry out the necessary physics filtering. In total, the ATLAS online selection consists of thousands of different individual triggers.
A trigger menu is a compilation of these triggers which specifies the physics algorithms to be used during data taking and the bandwidth a given trigger is allocated. Trigger menus reflect not only the physics goals of the collaboration for a given run, but also take into consideration the instantaneous luminosity of the LHC and limitations from the ATLAS detector readout and offline processing farm. For the 2017 run, the ATLAS trigger has been enhanced to be able to handle higher instantaneous luminosities (up to 2.0x10^{34}cm^{-2}s^{-1}) and to ensure the selection robustness against higher average multiple interactions per bunch crossing.
In this presentation, we describe the design criteria for the trigger menus used for Run 2 at the LHC. We discuss several aspects of the process, from the validation of the algorithms, the fine-tuning of the prescales, and the monitoring tools that ensure the smooth operation of the trigger during data-taking. We also report on the physics performance of a few trigger algorithms.
TBA
Faraday introduced electric field lines as a powerful tool for understanding the electric force, and field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, there is currently no field line theory that can be consistent with the complete theory of electromagnetism.
This work will discuss the notion of covariant electromagnetic field lines. We will show that it naturally extends electric field lines to general relativistic systems and derive a closed-form formula for the field lines curvature.
The curvature of electromagnetic field lines completely determines the dynamics of any electric charge and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminates all self-field singularities without using renormalization techniques.
Time permitting, the relationship between field lines curvature to gravity and/or quantum system will be discussed.
The BCS model is revisited and it is shown that the phenomenology predicted by it is much richer than it was thought before. I will show in realistic situations that the phase transition from the superconducting state to the normal (metal) state may be of the first order (the energy gap may have a jump at the phase transition), there may be two solutions for the energy gap equation, etc.
I show both, zero temperature [1] and finite temperature results [2].
[1] D. V. Anghel, arXiv:1609.07931.
[2] D. V. Anghel and G. A. Nemnes, Physica A 464, 74 (2016).
DM production in proton-proton collisions can be probed at the LHC by looking for missing energy signatures. We present an overview of the results from DM searches performed with the CMS experiment using proton—proton collision data collected during LHC Run 2 at a center of mass energy of 13 TeV. Signatures investigated include those yielding energetic jets and large missing transverse momentum as well as heavy flavour quarks plus missing transverse energy.
It is nowadays theoretically understood that in Quantum Mechanics (QM) the exponential decay is only an approximation. Deviations have been experimentally measured both at short and at long times. In turn, the non-exponential decay is responsible of the (also measured) Quantum Zeno Effect. Yet, an interesting open question, presented in this talk, is the emergence of non-exponential decay in the context of relativistic quantum field theory (QFT). Namely, this is the correct environment for creation and annihilation of particles. By using standard QFT techniques, we aim to evaluate the short-time behavior in a straightforward calculation. We shall find that non-exponential decay is also present in each QFT but is typically very small. An interesting exception is that of superrenormalizable theory, where deviations can be more sizable.
Recent LHC results on the appearance of sub-leading flow modes in PbPb collisions at 2.76 TeV, related to initial-state fluctuations, are analyzed and interpreted within the HYDJET++ model. Using the newly introduced Principal Component Analysis (PCA) method applied to two-particle azimuthal correlations extracted from the model calculations, the leading and the sub-leading flow modes are studied as a function of the transverse momentum ($p_{T}$) over a wide centrality range. The leading modes of the elliptic ($v^{(1)}_{2}$) and triangular ($v^{(1)}_{3}$) flow calculated within the HYDJET++ model reproduce rather well the $v_{2}\{2\}$ and $v_{3}\{2\}$ coefficients experimentally measured using the two-particle correlations. Within the $p_{T} \le $ 3 GeV/c range where hydrodynamics dominates, the sub-leading flow effects are greatest at t