A compendium of the most recent results obtained by the CMS collaboration on searches for supersymmetry is presented. The list comprises a combination of several searches for the electroweak production of winos, binos, higgsinos, and sleptons, the latest efforts devoted to analyses exploiting final states with multiple photons and jets, and a dedicated search for long-lived supersymmetric...
While the on-going Run-3 data-taking campaign will provide twice the integrated proton-proton luminosity currently available at the LHC, most of the data expected for the full LHC physics program will only be delivered during the HL-LHC phase. For this, the LHC will undergo an ambitious upgrade program to be able to deliver an instantaneous luminosity of $7.5\times 10^{34}$ cm$^{-2}$...
Many new physics models predict the existence of new particles. This talk summarizes recent ATLAS searches for Beyond-the-Standard-Model heavy resonances which decay to pairs of bosons, heavy quarks, or leptons, using Run 2 data collected at the LHC. The experimental methods are explained, including the jet substructure techniques used in some searches to disentangle the hadronic decay...
Many theories beyond the Standard Model (BSM) have been proposed to address several of the Standard Model shortcomings, such as the origin of dark matter and neutrino masses, the fine-tuning of the Higgs Boson mass, or the observed pattern of masses and mixing angles in the quark and lepton sectors. Many of these BSM extensions predict new particles or interactions directly accessible at the...
Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. Naturalness arguments favour supersymmetric partners of the gluons and third generation quarks with masses light enough to be produced at the LHC. This talk will present the latest results of searches conducted by the...
An overview of the latest results on $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay and precision measurements at the NA62 experiment will be presented.
The NA62 experiment at CERN collected the world’s largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the Branching Fraction of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates....
AtlFast3 is the new, high-precision fast simulation in ATLAS that was deployed by the collaboration to replace AtlFastII, the fast simulation tool that was successfully used for most of Run2. AtlFast3 combines a parametrization-based Fast Calorimeter Simulation and a new machine-learning-based Fast Calorimeter Simulation based on Generative Adversarial Networks (GANs). This presentation will...
Processes involving quartic electroweak gauge couplings have become experimentally accessible for the first time in the run-2 dataset of the LHC. In this talk, recent measurements of triboson production and the electroweak diboson production in association with two jets by the ATLAS experiment are presented. Differential measurements of Zyy production, as well as the observation of Wyy and WZy...
The increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to $L \simeq 7.5 \times 10^{34}$ cm$^{−2}$s$^{−1}$ will have a severe impact on the ATLAS detector reconstruction and trigger performance. The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer momentum resolution will be particularly...
From 7 naturally occurring Nd isotopes, 5 are unstable in relation to α decay. Only for 144Nd, α decay was experimentally registered (to the ground state of the daughter nucleus), with half-life measured as 2.3x10^15 y [1]. This value is in a good agreement with our calculations. Theoretical T1/2 estimations of possible transitions for other Nd isotopes are higher. If these decays are...
In this work, we employ relativistic flux tube model to investigate the mass spectra of heavy-light baryons in quark-diquark configuration. Modified Regge relation between mass and angular momentum is derived by means of semiclassical approach in relativistic flux tube model. The mass spectra is generated by including spin dependent interactions in j-j coupling scheme. Regge trajectories in...
The μΝet project aims to deploy and operate an extensive school network of educational Cosmic Ray telescopes throughout the Peloponnese region. As part of the Net project, an extended educational program was conducted, with educational activities focusing on the design, construction, testing, and operation of Cosmics detectors (microCosmics), as well as the remote operation of cosmic ray...
Although the standard model (SM) of particle physics provides a remarkably accurate description of phenomena associated with the known elementary particles and their interactions, it leaves significant problems unresolved, which motivates a comprehensive program of searches for beyond-the-SM physics at high energy colliders. This talk presents searches in CMS for new phenomena in the final...
Recent results on top quark properties and interactions are presented, obtained using data collected with the CMS experiment at 13 TeV and 13.6 TeV pp center-of-mass energies. The first measurement of the top quark pair cross section at 13.6 TeV is done with data collected by the CMS experiment, in good agreement with the standard model prediction. The first observation of the production of...
The ASACUSA collaboration at CERN's Antiproton Decelerator has carried out laser spectroscopy of metastable antiprotonic helium atoms embedded in superfluid helium targets [1]. These are three-body Coulomb systems composed of a helium nucleus, an electron and an orbital antiproton. An abrupt and unexpected reduction in the linewidth of the antiprotonic laser resonance to sub-Ghz width was...
New results from the DANSS experiment on the searches for sterile neutrinos are presented. They are based on 7 million inverse beta decay events collected at 10.9, 11.9, and 12.9 meters from the 3.1 GW reactor core of the Kalinin Nuclear Power Plant in Russia. Additional 1 million of antineutrino events further improves the sensitivity for the sterile neutrino mixing parameter below 0.01 for a...
At the CMS experiment, the identification of heavy flavor jets, i.e. jets originated from bottom and charm quarks, is crucial for many Standard Model (SM) measurements, mostly involving the top quark and the Higgs boson studies, and searches for new physics. The CMS collaboration developed extremely powerful jet tagging algorithms based on deep learning methods, which state-of-the-art will be...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has been able to reach the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of...
The KM3NeT research infrastructure includes two underwater Cherenkov telescopes in the Mediterranean Sea, ARCA (Astroparticle Research with Cosmics in the Abyss) and ORCA (Oscillation Research with Cosmics in the Abyss). The detectors are still under construction but currently taking data and the first physics results were already obtained. The detection technology is the same for both...
The $U(1)_{T 3R}$ extension of the Standard Model is an attractive formulation that addresses the mass hierarchy between the third and the first two generations of fermions, explains thermal dark matter abundance, and the muon $g - 2$ and $R_{K^{(*)}}$ anomalies. The model contains a dark matter candidate scalar boson, the $\phi$ particle, and a vector-like quark (a scalar and vector...
Kaonic atoms are exotic atoms formed when a negatively charged kaon (K$^{-}$) is stopped in a target and captured by the atomic system, replacing the electron in a highly excited level. The captured K$^{-}$ initiates an electromagnetic cascade down to the innermost levels of the atom. As the innermost levels are approached, the strong interaction between the kaon and nucleons induces energy...
This talk provides an overview of the applications of machine learning (ML) techniques within the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The CMS experiment generates vast amounts of data, and machine learning has emerged as a powerful tool for data analysis, event reconstruction, anomaly detection, and optimization. In this talk, we highlight the various...
Recent data from SND at VEPP2000 on cross-sections of the electron-positron annihilation to different hadronic states in the energy range 1 -- 2 GeV will be presented. Processes e+e- -> pi+pi-pi0, e+e- -> оmega pi0 -> pi+pi-pi0pi0, e+e- -> eta pi+ pi- 2pi0, e+e- -> eta eta gamma, e+e- -> pi0 gamma, e+e- -> K+K-pi0, e+e- -> eta'gamma, e+e- -> N-antiN and other were studied.
We propose a model of dynamical symmetry breaking, in which a new type of fundamental scalar fields of zero mass-dimension mediate the couplings of fermions to the gravitational field, represented here as a tetrad field in the same manner as Riemann-Cartan gravity. In our model, the tetrad couples to the standard model fermions non-minimally, and the very coupling coefficients are the...
In the recent past, a substantial effort has been devoted into the understanding of
lepton mixing and masses through flavour symmetries. While non-abelian discrete symmetries have been shown to explain the current pattern of neutrino mixings, no real illumination was sparked on the
problem of flavor as we can reproduce in many different ways the observations. In this talk I will discuss the...
The remarkably large dataset collected with the ATLAS detector at the highest proton-proton collision energy provided by LHC allows to use the large sample of top quark events to test theoretical predictions with unprecedented precision. Recent measurements of total and differential top-quark cross sections as well properties of top-quark production are presented, including new measurements of...
Electron mass is considered as a matrix element
of the energy–momentum trace in the rest frame. The diagrams for this matrix element are different from the textbook diagrams for the electron mass renormalization. We clarify connection between the two sets of diagrams and explain analytically and diagrammatically why the results
of both calculations coincide.
Active learning techniques can enhance efficiency in new physics searches. To demonstrate this an extended two dimensional search using an active learning technique with a preserved analysis is presented. This preserved analysis searches for a dark-Z boson in four-lepton final states. Bayesian optimization is applied in the active learning process to look for the maximal difference between the...
CMS selects interesting events using a two-tiered trigger system. The first level (L1), composed of custom hardware processors, uses information from the calorimeters and muon detectors to select events at a rate of around 110 kHz within a fixed latency of about 4\mus. The second level, the high-level trigger (HLT), consists of a farm of processors running a version of the full event...
The Liquid Argon Calorimeters are employed by ATLAS for all electromagnetic calorimetry in the pseudo-rapidity region |η| < 3.2, and for hadronic and forward calorimetry in the region from |η| = 1.5 to |η| = 4.9. They also provide inputs to the first level of the ATLAS trigger. After successful period of data taking during the LHC Run-2 between 2015 and 2018 the ATLAS detector entered into the...
This talk presents precise measurement of the properties of the Higgs boson, including its mass, total width, spin, and CP quantum number. The measurements are performed in various Higgs boson production and decay modes, as well as their combinations. Observation of deviations between these measurements and Standard Model (SM) predictions would be a sign of possible new phenomena beyond the SM
More than a decade later and counting since the announcement by the CMS and ATLAS collaborations at the CERN Large Hadron Collider of the observation of a Higgs boson at a mass of around 125 GeV, the dataset collected has allowed to determine its mass, measure its production cross-sections in various modes, observe numerous of its fermionic and bosonic decay channels, and establish its...
The discovery of the Higgs boson with the mass of 125 GeV confirmed the mass generation mechanism via spontaneous electroweak symmetry breaking and completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many experimental measurements, it is not capable of solely explaining some observations. Many extensions of the Standard...
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and...
The MicroBooNE experiment utilizes an 85-ton active volume liquid argon time projection chamber (LArTPC) neutrino detector. It can distinguish between photons and electron electromagnetic showers and can select charged current electron neutrino and muon neutrino events with exceptional performance. In this talk, we will presentresults on MicroBooNE's investigation of the MiniBooNE Low Energy...
The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association...
Resistive Plate Chamber detectors in HEP and beyond are usually operated with high-performance gas mixtures, containing a relevant fraction of C2H2F4 plus SF6, both greenhouse gases characterized by a very high global warming potential.
Since a few years the RPC EcoGas@GIF++ Collaboration has put in place a big effort to investigate RPCs performance with new, eco-friendly, gas mixtures...
The event rates and kinematics of Higgs boson production and decay processes at the LHC are sensitive probes of possible new phenomena beyond the Standard Model (BSM). This talk presents precise measurements of Higgs boson production and decay rates, obtained using the full Run 2 and partial Run 3 pp collision dataset collected by the ATLAS experiment at 13 TeV and 13.6 TeV. These include...
Hadronic object reconstruction is one of the most promising settings for cutting-edge machine learning and artificial intelligence algorithms at the LHC. In this contribution, selected highlights of ML/AI applications by ATLAS to particle and boosted-object identification, MET reconstruction and other tasks will be presented.
The production of jets and prompt isolated photons at hadron colliders provides stringent tests of perturbative QCD. The latest measurements by the ATLAS experiment, using proton-proton collision data at $\sqrt{s}$ =13 TeV, are presented. Prompt inclusive photon production is measured for two distinct photon isolation cones, R=0.2 and 0.4, as well as for their ratio. The measurement is...
The Positron Annihilation into Dark Matter Experiment (PADME) is a fix-target experiment ongoing at the Laboratori Nazionali di Frascati of INFN whose main goal is searching for dark matter signals in electron-positron annihilations in the MeV mass range [1].
First sets of physics-grade data have been collected over the last few years with the main goal to look for a Dark Photon in the...
Monitored neutrino beams represent a powerful and cost effective tool to suppress cross section related systematics for the full exploitation of data collected in long baseline oscillation projects like DUNE and Hyper-Kamiokande. In the last years the NP06/ENUBET project has demonstrated that the systematic uncertainties on the neutrino flux can be suppressed to 1% in an accelerator based...
Non-linear field theories often possess so-called soliton solutions that have localized energy densities and that are characterized by topological charges. Quantum corrections to the total energy may be decisive for the stability of solitons with higher charges.To explore this stability I will consider vortices in scalar electrodynamics which is one of the rare renormalizable models that...
In the high energy limit of scattering amplitudes in QCD, the Feynman diagrams with the dominant contributions are those which can be described as composite state of two or more reggeized gluons (Reggeons). After revisiting the concept of Feynman diagram complexity in the high energy effective field theory, we study its emerging scaling laws for the case of two, three and four interacting...
The Phase-II Upgrade of the LHC will increase its instantaneous luminosity by a factor of 7 leading to the High Luminosity LHC (HL-LHC). At the HL-LHC, the number of proton-proton collisions in one bunch crossing (called pileup) increases significantly, putting more stringent requirements on the LHC detectors electronics and real-time data processing capabilities.
The ATLAS Liquid Argon...
After two decades of RHIC running as a polarized proton collider, we summarize recent achievements of the PHENIX spin program and their impact on our understanding of the nucleon’s spin structure on partonic level (e.g. quark and gluon spin contribution to the spin of the proton), and transverse spin phenomena giving access to parton dynamics within the nucleon. Of particular interest are...
The high center-of-mass energy of proton-proton collisions and the large available datasets at the CERN Large Hadron Collider allow to study rare processes of the Standard Model (SM) with unprecedented precision and search for new physics that might enhance extremely rare processes in the SM. Measurements of rare SM processes provide new tests of the SM predictions with the potential to unveil...
The ATLAS experiment has performed extensive searches for rare Standard Model processes involving top quarks. In this contribution two recent highlights of this programme are presented. The top-quark pair production in association with a W boson is a difficult process to calculate and model and is one of the leading sources of same-sign and multi-lepton events. To improve our understanding of...
The CMS inner tracking system consists of Silicon Pixel and Silicon Strip detectors. The tracker is designed to measure the trajectory of the charged particles tracks. The pixel detector provided high-quality physics data during the LHC Run 2, finishing with a detector live fraction of 95% and hit efficiency of >99% in all but the innermost layer. After the end of Run 2 in 2018, a thorough...
With the end of RUN-2, the LHC has delivered only 4% of the collision data expected to be available during its lifetime. The now ongoing data-taking campaign -- RUN-3 -- will more than double the integrated luminosity the LHC accumulated during Runs 1 and 2. The Run-3 will be the herald of the HL-LHC era, an era when 90% of total LHC integrated luminosity (3 to 4 ab$^{-1}$) will be...
In response to the High Luminosity upgrade of the Large Hadron Collider (HL-LHC), which is expected to deliver an instantaneous luminosity up to 7 times higher with respect to the nominal value, the muon system of the CMS experiment will undergo specific upgrades targeting both the electronics and detectors. The goal is to cope with the new challenging data-taking conditions, maintaining and...
The MIP Timing Detector (MTD) is a new sub-detector planned for the Compact Muon Solenoid (CMS) experiment at CERN, aimed at maintaining the excellent particle identification and reconstruction efficiency of the CMS detector during the High-Luminosity LHC (HL-LHC) era. The MTD will provide new and unique capabilities to CMS by measuring the time-of-arrival of minimum ionizing particles with a...
Precision luminosity measurements are an essential ingredient to cross section measurements at the LHC, needed to determine fundamental parameters of the standard model and to constrain or discover beyond-the-standard-model phenomena. The latest luminosity measurements of the CMS detector at the CERN Large Hadron Collider are reported. The absolute luminosity scale is obtained with...
Recent results for dark matter searches with the CMS experiment.
This review lecture focuses on the role the Nambu-Goldstone bosons of some spontaneously broken accidental global symmetries may play in particle physics and cosmology. Beginning with the possibility
that the Higgs boson may be a pseudo-Nambu-Goldstone boson, they may also include a QCD axion solving the strong
CP problem. Axion-like-particles are good candidates for dark matter and may...
The REDTOP experiment is a super-$\eta$/$\eta'$ factory aiming at exploring physics BSM, and Cold Dark Matter in particular, in the MeV-GeV energy range. This range is, at present, the most unconstrained among the energy regions searched by current and planned experiments.
The $\eta$ and $\eta'$ mesons are almost unique in the particle universe. Their quantum numbers are all zero, which...
Neutrino oscillation physics has now entered the precision era. In parallel with needing larger detectors to collect more data, future experiments further require a significant reduction of systematic uncertainties with respect to what is currently available. In the neutrino oscillation measurements from the T2K experiment, the systematic uncertainties related to neutrino interaction cross...
Precision measurements using the leptonic decays of W and Z boson at the LHC are used to determine the fundamental parameters of the Standard Model. In this talk, extraordinarily precise double-differential measurement of the Z boson production in the full phase space of the decay leptons at a centre-of-mass energy of 8 TeV will be presented. The recoil of the Z-boson is sensitive to quark and...
Various theories beyond the Standard Model predict new, long-lived particles with unique signatures which are difficult to reconstruct and for which estimating the background rates is also a challenge. Signatures from displaced and/or delayed decays anywhere from the inner detector to the muon spectrometer, as well as those of new particles with fractional or multiple values of the charge of...
The direct production of electroweak SUSY particles, including sleptons, charginos, and neutralinos, is a particularly interesting area with connections to dark matter and the naturalness of the Higgs mass. The small production cross-sections and challenging experimental signatures lead to difficult searches. This talk will highlight the most recent results of searches performed by the ATLAS...
I will discuss about recent B-physics results from the CMS Collaboration.
LHCb is a dedicated b-physics experiment at the CERN Large Hadron Collider (LHC).
Designed to perform precision measurements of CP violation as well as rare decays of beauty and charm hadrons, its detector was successfully operated during Run 1 and Run 2 of the LHC and is currently taking data after having being upgraded to run at a luminosity of 2×10^33cm−2s−1. A further upgrade phase,...
The Micromegas detectors are part of the New Small Wheel (NSW) system of the ATLAS experiment, the largest upgrade project of Phase-1. Together with sTGC detectors they provide trigger and tracking capability in the innermost station of the end-cap part of the Muon spectrometer.
The Micromegas detector of ATLAS cover an active area of about 1280 m^2, has 1024 HV channels and 2.1 M readout...
The instantaneous luminosity of the Large Hadron
Collider at CERN will be increased by about a factor
of five with respect to the design value by
undergoing an extensive upgrade program over the
coming decade. The largest phase-1 upgrade project
for the ATLAS Muon System was the replacement of the
first station in the forward regions with the New
Small Wheels (NSWs) which took place...
Experimental uncertainties related to hadronic object reconstruction can limit the precision of physics analyses at the LHC, and so improvements in performance have the potential to broadly increase the impact of results. Recent refinements to reconstruction and calibration procedures for ATLAS jets and MET result in reduced uncertainties, improved pileup stability and other performance gains....
Perturbative solutions for unpolarized QED parton distribution and fragmentation functions are presented explicitly in the next-to-leading logarithmic approximation. The scheme of iterative solution of QED evolution equations is described in detail. Terms up to $\mathcal{O}(\alpha^3L^2)$ are calculated analytically, where $L=\ln(\mu/m_e^2)$ is the large logarithm which depends on the...
Application of non-extensive Tsallis statistics to study spectra of particles produced in proton-proton or nucleus-nucleus collisions at relativistic energies becomes very popular nowadays. In present work we fit the transverse momentum spectra of hadrons from intermediate heavy-ion collisions, generated by two microscopic transport models, UrQMD and SMASH, to Tsallis distribution. The...
In SU(3) lattice QCD, we study the effective potential (thermodynamic
potential) of thermal quenched QCD in term of the Polyakov loop in the
field theoretical manner for the first time. We adopt SU(3) lattice
with beta=5.893 and 64*36, just corresponding to the critical
temperature of the deconfinement phase transition. The effective
potential is numerically evaluated using the...
During LHC Run2, the CMS detector was operated at the highest instantaneous luminosity. These conditions posed significant demands on the electromagnetic calorimeter (ECAL). Precision alignment, calibration, monitoring and accurate reconstruction are essential to provide a precise measurement of electron and photons, that in turn are key to a variety of physics analysis, ranging from Standard...
The $2\beta$ decay of $^{150}$Nd to the first excited 0$^{+}_{1}$ level of $^{150}$Sm (E$_{exc}$ = 740.5 keV) was studied using a low-background experimental setup composed of four HPGe detectors (volume $\simeq$ 225 cm$^{3}$ each) located in the STELLA facility at the Gran Sasso National Laboratories of INFN. A highly purified sample of Nd$_{2}$O$_{3}$ (mass 2.38 kg) was measured for 51237...
Recently there has been considerable interest in the development of crystal scintillators of the Cs$_2$MCl$_6$ family of metal hexachlorides (M = Hf or Zr) due to their exceptional properties: a high light yield (up to 35000 photons/ MeV ), good linearity in the energy response, excellent energy resolution ($< 3.5\%$ at 662 keV in the best configuration) and excellent ability to discriminate...
Understanding the contribution of gluons to the spin of the proton is crucial for unraveling the proton spin puzzle. This has been one of the primary motivations behind the spin program conducted at the Relativistic Heavy Ion Collider (RHIC). The longitudinal spin structure of the proton is probed by colliding two protons with longitudinal polarization ($\vec{p}+\vec{p}$) and measuring the...
A new era of hadron collisions will start around 2029 with the High-Luminosity LHC which will allow to collect ten times more data than what has been collected during 10 years of operation at LHC. This will be achieved by higher instantaneous luminosity at the price of higher number of collisions per bunch crossing.
In order to withstand the high expected radiation doses and the harsher...
We investigate the multiplicity fluctuations of charged particles observed in high-energy nuclear collisions and relate them to the size of hadronizing systems which happen during such processes. We use the average multiplicities N and variances Var (N) of multiplicity distributions of charged particles produced in centrality selected collisions of relativistic heavy-ion nuclei to evaluate the...
I shall address some of the main lessons drawn so far from the tadpole potentials that emerge in the ten–dimensional strings with broken supersymmetry. These lessons include weak-string-coupling cosmologies that appear to provide clues on the onset of the inflation and spontaneous compactifications to lower–dimensional Minkowski spaces at corresponding length scales. The cosmological solutions...
The light pseudoscalar mesons π0, η and ηꞌ provide a unique laboratory to probe fundamental QCD symmetries at the confinement scale. While π0 and η are Goldstone bosons due to spontaneous chiral symmetry breaking, ηꞌ is not due to an axial U(1) anomaly coupling to the gluon field. The chiral anomaly coupling to the electromagnetic field drives the two-photon decays of these mesons. This...
