Choose timezone
Your profile timezone:
Powered by Indico
v3.3.5-pre
Help us make Indico better by taking this survey! Aidez-nous à améliorer Indico en répondant à ce sondage !
The U.S. particle physics community is proud to host the 38th ICHEP in Chicago from the 3rd to the 10th August 2016. ICHEP is a focal point of the field of particle physics, bringing together experimentalists and theorists of the world. It was first held in 1950, and is biennial since 1960.
| Dates: | from 3 August 2016 17:00 to 10 August 2016 17:50 |
|---|---|
| Timezone: | US/Central |
| Location: |
Sheraton Grand Chicago |
| Address: | 301 East North Water Street Chicago IL 60611 USA |
A search for new physics is performed based on multijet events with large missing transverse momentum produced in 13 TeV proton-proton collisions. The data sample, corresponding to an integrated luminosity of 2.2 fb-1, was collected with the CMS detector at Run 2 of the CERN LHC. The data are examined in search regions of jet multiplicity, bottom-quark jet multiplicity, missing transverse momentum, and the scalar sum of jet transverse momenta. Exclusion limits are presented for simplified supersymmetric models of gluino pair production.These results significantly extend the limits from LHC Run 1.
Results are reported from a search for supersymmetric particles in pp collisions in the final state with a single, high pT lepton; multiple jets, including at least one btagged jet; and large missing transverse momentum. The data sample corresponds to 2.1 fb-1 recorded by the CMS experiment at ps = 13 TeV. The search focuses on processes leading to high jet multiplicities, such as gluino pair production with the gluino decaying to top quarks. The quantity MJ, defined as the sum of the masses of the large-radius jets in the event, is used in conjunction with other kinematic variables to provide discrimination between signal and backgrounds and as a key part of the background estimation method. Competitive exclusion limits are obtained.
We present a search for new physics in events with one or two low-momentum leptons and missing transverse energy, based on the first proton-proton integrated luminosity recorded with the CMS detector at 13 TeV. The final state can be the phenomenology of SUSY models foreseeing a small mass splitting between the lightest supersymmetric particle and e.g. the top squark or chargino, in the so called compressed mass spectra scenario. The event selection and kinematics, together with methods for estimating the standard model backgrounds are presented. Results are interpreted in terms on SUSY models where a compressed mass scenario is foreseen.
We study detector performance of Higgs boson identification variables at very high energy proton colliders. We study Higgs bosons decaying to bottom quarks with transverse momentum in the multi-TeV range. Detectors are benchmarked in various configurations in order to understand the impact of granularity and resolution on boosted Higgs boson discrimination.
Current experiments measuring CP asymmetries in $D$ meson decays approach a sensitivity which is comparable to the tiny Standard-Model (SM) predictions for these quantities. However, the errors of the SM predictions, which essentially all rely on the approximate SU(3) flavour symmetry, make the search for new physics in $D$-meson CP asymmetries difficult. I present new calculations which control the dominant hadronic uncertainties up to linear order in SU(3) breaking. I further discuss the potentially large CP asymmetry in $D^0 \to K_S K_S$.
Precision measurements are presented of the top-quark pair inclusive production cross section in proton-proton collisions at the LHC at centre-of-mass energies of 7, 8 and 13 TeV. The data are collected with the CMS experiment during the years 2011, 2012, and 2015. The analyses profit from different top quark final states and make use of events with two, one or no reconstructed charged leptons. In most analyses b-jet identification is used to increase the purity of the selection. The backgrounds are determined using data-driven techniques. The results are combined with each other and compared with theory predictions. Indirect constraints on both the top quark mass and alpha_s are obtained through their relation to the inclusive cross section.
Differential top quark pair production cross sections are measured in proton-proton collisions at the LHC at centre-of-mass energies of 7, 8, and 13 TeV, using data collected by the CMS experiment in the years 2011, 2012, and 2015. The differential cross sections are measured as functions of various kinematic observables, including the transverse momentum and rapidity of the (anti)top quark and the top-antitop system and the jets and leptons of the event final state. Multiplicity and kinematic distributions of the jets produced in addition to the top pair are investigated. Measurements of the associate production of top quark pairs with additional b-quarks, and a search for four-top production are also presented.
State-of-the-art theoretical predictions accurate to next-to-leading order QCD interfaced with Pythia8 and Herwig++ event generators are tested by comparing the unfolded ttbar differential data collected with the CMS detector at 8 TeV. These predictions are also compared with the underlying event activity distributions in ttbar events using CMS proton-proton data collected in 2015 at a center of mass energy of 13 TeV.
Training session for volunteers for library program. Stop by for 30 minutes when you have time to learn about your presentation.
Searches for the direct electroweak production of supersymmetric charginos and neutralinos in topologies containing leptons and W, Z, and Higgs bosons are presented.
A search for direct top squark pair production in the hadronic final state is presented. The data used are 2.3 fb-1 of pp collision data at 13 TeV taken with the CMS detector in 2015.
Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the third generation quarks with masses not too far from those of their Standard Model counterparts. Top or bottom squarks with masses of a few hundred GeV can also give rise to large direct pair production rates at the LHC. The recent increase in the center of mass energy of the proton-proton collisions gives a unique opportunity to extend the sensitivity to production of supersymmetric particles at the Large Hadron Collider. The talk presents recent ATLAS results from searches for direct stop and sbottom pair production, with emphasis on those obtained using proton-proton collisions at a centre-of-mass energy of 13 TeV.
Charmless hadronic B decays constitute a powerful probe to search for new physics beyond the standard model and provide constraints of various CP violation parameters. We report the final measurements from Belle of the branching fraction and CP asymmetry for a variety of charmless decays -- $B^0 \to \pi^0\pi^0$, $B^+ \to K^+ K^- \pi^+$, $B\to \phi \phi K$, and $B^+ \to K_S^0 K_S^0 h^+$ $(h=K,\pi)$ -- as well as a search for the $B^0 \to \eta\eta$ decay. All investigations employ the full dataset at $\Upsilon(4S)$ delivered by the KEKB $e^+ e^-$ collider. The $B^0 \to \pi^0 \pi^0$ measurement enables improved constraints on the CKM unitarity triangle $\phi_2$. For $B^+ \to K^+ K^- \pi^+$ we measure CP asymmetry as a function of the invariant mass of the $K^+ K^-$ system, where LHCb has earlier reported an unexpectedly strong enhancement at low mass. The three-body decays $B^+ \to K_S^0 K_S^0 h^+$ $(h=K,\pi)$ and $B\to \phi \phi K$ both proceed predominantly via flavor-changin!
g neutral current transitions and hence are sensitive to potential new physics effects. The $B^0 \to \eta\eta$ decays could play an important role in understanding the $B$ decay dynamics and improving the deviation boundary of $\sin 2\phi_1$ measured in $b\to s c\bar{c}$ and $b\to s q\bar{q}$ decays.
Charmless $B_s$ decays are studied using a data sample of 121 fb−1 collected at the Υ(10860) resonance ($\sqrt{s} = 10.87$ GeV) at Belle. We present the branching fraction of $B_s \to K^0 \bar{K}^0$, which is the first observation of a charmless two-body $B_s$ decays involving only neutral hadrons in the final state. Also presented is the first search for $B_s \to \eta\eta$ decay.
Knowledge on the angles of the Unitarity Triangle provides stringent tests on the Standard Model of electroweak interactions and enables one to constrain potential effects of the physics beyond. The parameter $\sin (2\beta) = \sin (2\phi_1)$ has been precisely measured by the B factory experiments BaBar and Belle using $b \to c \bar{c} s$ transitions such as the golden mode $B^0 \to J/\psi K_S^0$. In terms of the angle $\beta = \phi_1$, the value smaller than $\pi/2$ is favored between two possible solutions, however the discrimination is not evident yet at current experimental status. By reconstructing the neutral $D$ meson decays in self-conjugated multi-body final states, a time-dependent Dalitz analysis in $B^0 \to D^{(*)} h^0$ decays provide a theoretically clean probe to constrain $\cos(2\beta) = \cos(2\phi_1)$. We present a time-dependent Dalitz analysis of $B^0 \to D^{(*)} h^0$ decays followed by the $D$ meson decays to $K_S^0 \pi^+ \pi^-$ where the $h^0$ is a $\pi i^0$, $\eta$ or $\omega$ meson. The measurement is performed by combining the final data samples of $471 \times 10^6$ $B\overline{B}$ pairs and $772 \times 10^6$ $B\overline{B}$ pairs recorded by the BaBar and the Belle experiments, respectively.
Measurements are presented of the properties of top quarks in pair production from proton-proton collisions at the LHC. The data were collected at pp centre-of-mass energies of 7 and 8 TeV by the CMS experiment during the years 2011 and 2012. The charge asymmetry is measured using the difference of the absolute rapidities of the reconstructed top and anti-top kinematics, as well as from distributions of the top quark decay products. The measurements are performed in the decay channels of the ttbar pair into both one and two leptons in the final state. The results, obtained differentially in several kinematic variables of the ttbar-system, are discussed in the context of the forward-backard asymmetry measurements at Tevatron. The polarization of top quarks is measured from the decay angular distributions. Ttbar spin correlation and asymmetries are measured from the angular distributions of the top quark decay products. These measurements are used to search for new physics. TTbar spin correlation is also measured using a matrix element method. Measurements of the associate production of top quark pairs with vector bosons (photons, W and Z) are also presented. The results are compared with standard model predictions.
Several measurements of top quark properties in top quark decays are presented using data collected by the CMS experiment during the years 2011 and 2012. The polarization of W bosons in top quark decays is measured. The W-boson helicity fractions and angular asymmetries are extracted and limits on anomalous contributions to the Wtb vertex are determined. Furthermore, searches for flavor-changing neutral currents in top quark decays are presented using samples of top-quark pair event candidates decaying via Wb and Zq into lνb and llq events, or decaying via Hq into 3 b-quarks. The flavor contents in top-quark pair events are measured using the fraction of top quarks decaying into a W-boson and a b-quark relative to all top quark decays, R=BR(t->Wb)/Sum(BR(t->Wq)), and the result is used to determine the CKM matrix element Vtb as well as the width of the top quark resonance. The top-quark charge is measured, using the charge correlations between high-pT muons from W boson decays and soft muons from B-hadron decays in b jets. We also report on searches for CP violation effects in ttbar.
The integration of HPC resources into the standard computing toolkit of HEP experiments is becoming important as traditional resources are being outpaced by the needs of the experiments. We will describe solutions that address some of the difficulty in running data-intensive pipelines on HPC systems. Users of NERSC HPCs are benefiting from a newly developed package called "Shifter" that creates docker-like images and the deployment of the new "Burst Buffers" NVRAM file system designed to offer extreme I/O performance, supporting terabyte-per-second bandwidth and 10s of millions of IO operations per second. These tools have enabled particle physicists from multiple experiments routinely run their entire multi-TB sized CVMFS software stacks across tens of thousands of compute cores. In addition, an Edge Service has been developed to provide a uniform interface for HEP job management systems to access supercomputer sites. It is based on the Python Django framework and is composed of two processes, of which one runs inside the supercomputing environment and one runs outside. It has been used to run over 100 million core-hours of LHC experiment jobs on the Mira supercomputer at the Argonne Leadership Computing Facility and on the Edison supercomputer at NERSC for LHC experiments.
A variety of vector boson measurements has been performed with Run 1 LHCb data, including inclusive Z/W cross-sections, the Z forward-backward asymmetry, Z plus charm, Z/W production with jets (including heavy flavor), and top production. Additionally, new inclusive Z/W cross-sections have been measured with Run 2 data. A summary of the most relevant results will be presented.
Text coming
We present a search for supersymmetry in diphoton plus jets plus missing transverse energy final states. The analysis uses data collected with the CMS detector at a center-of-mass energy of 13 TeV.
Merged abstract
Text coming
Text coming
The Belle II experiment aims to record 50 ab$^{-1}$ data with the high
luminosity to be provided by the SuperKEKB energy-asymmetric $e^+e^-$
collider. The anticipated high statistics data enables us to perform
studies of $B$ decays involving $\tau$ leptons such as
$B^+ \to \tau^+ \nu_{\tau}$ and $B \to D^{(*)} \tau^+ \nu_{\tau}$ modes.
The precise measurements of branching fraction as well as the $\tau$
lepton polarization in these $B$ decays provide a very sensitive indirect
search for a charged Higgs boson. Belle IIs's sensitivity for the charged
Higgs is complementary to direct searches at ATLAS and CMS.
Measurements are presented of t-channel single top quark production in proton-proton collisions at the LHC at centre-of-mass energies of 7, 8 and 13 TeV, using data collected with the CMS experiment during the years 2011, 2012 and 2015. The analyses consider leptonic decay channels of the W from the top decays, and makes use of kinematic characteristics of electroweak single top production for the separation of signal from backgrounds using multivariate methods. The measurement is used to constrain the Vtb CKM matrix element. The results are compared with the most precise standard model theory predictions. The inclusive fiducial cross section is also measured. Measurements of top/antitop cross section ratio and of various differential single top quark production cross sections are also presented.
Measurements of single top quark production in the tW-channel in pp collisions are presented. In the tW-channel a top quark is produced in association with a W boson. The data were collected in the years 2011 and 2012 at centre-of-mass energies of 7 and 8 TeV. The experimental signature is similar to top pair production, and there is interference at higher orders between the two processes. The measurements are performed using final states in which the associated W boson as well as the one originating from the top quark decay leptonically. Multivariate methods are used to extract the cross section. The result is compared with current standard model theory predictions. The measurement is used to constrain the Vtb CKM matrix element. Furthermore, a search for s-channel single top production at 8 TeV is presented.
Early-career scientists from Fermilab will discuss physics, life and career with students attending the ASP.
We consider a dark sector with SU(3)C×U(1)Y×U(1)X and three families of dark fermions that are chiral under dark U(1)X gauge symmetry, whereas scalar dark matter X is the SM singlet. U(1)X dark symmetry is spontaneously broken by nonzero VEV of dark Higgs field ⟨Φ⟩, generating the masses of dark fermions and dark photon Z′. The resulting dark Higgs boson ϕ can be produced at the LHC by dark quark loop (involving 3 generation) and will decay into a pair of photon through charged dark fermion loop. Its decay width can be easily ∼45 GeV due to its possible decays into a pair of dark photon, which is not strongly constrained by the current LHC searches pp→ϕ→Z′Z′ followed by Z′ decays into the SM fermion pairs. The scalar DM can achieve thermal relic density without conflict with direct detection bound or the invisible ϕ decay into a pair of DM.
Merged abstract
Our understanding of the transition from partons to hadrons in QCD has been challenged in recent years. In particular for high-multiplicity minimum-bias events at the LHC, novel experimentation techniques have revealed tantalising indications of non-trivial and possibly collective phenomena. A new wave of model building efforts has ensued, including ideas of colour reconnections, colour ropes, interacting strings, and hydrodynamics. It is essential to develop further sensitive probes of the mechanisms underpinning this fundamental aspect of QCD, to find answers to key questions such as if and how jet universality is broken and whether thermalisation is relevant in pp collisions. The answers will not only be of fundamental interest but will also impact precision studies that rely on hadronisation models, as well as the interpretation of heavy-ion results that use pp collisions as a reference. Using strangeness and baryons as tracers, we propose an extension of minimum-bias studies adapted to the environment of the underlying event which show substantial discriminatory power between several alternative models of soft physics. The applicability of this and related works to improve soft physics modelling at the LHC is explored.
The LBNF at Fermilab would deliver a 1.2MW neutrino beam to the
DUNE experiment, allowing an unprecedented reach in neutrino oscillation
physics and providing a unique opportunity to effect a generational advance
in the fundamental measurements of neutrino induced fundamental interactions
at the near site. We shall review salient topics among these interactions.
Prospects for new physics at the near site will be presented.
We study the dark matter particle, the dark photon (DP), in the decay of the Higgs-like boson. The nature of dark matter is maintained through the hidden sector including the effects of breaking of the scale invariance. The model is based on the additional $U^{\prime}(1)$ gauge group associated with light DP.
The interaction between DP and quarks is mediated by the derivative of the scalar - the dilaton. The latter appears in the conformal sector which triggers the electroweak symmetry breaking.
Upper limits are set on the DP mass, the mixing strength between the standard photon and DP. The model does allow to estimate the DP mass with the value of 4.5 MeV. The maximal value of the scale invariance breaking constant is also reported.
Searches in CMS for dark matter in final states with invisible particles recoiling against jets, top/bottom quarks, Ws, Zs, photons are presented. Various topologies are explored, covering several specific dark-matter production modes. The combination in a simplified-model framework of various searches for direct dark matter production with the CMS detector is discussed, highlighting sensitivities of the analyses under various assumptions of DM production and complementarities with non-DM analyses.
Results of searches for both prompt and non-prompt leptonic decays of new
dark sector particles in proton-proton collisions with the ATLAS detector
at a center-of-mass energy of 13 TeV are presented. Searches that
encompass a wide range of new particle masses, lifetimes and degrees of
collimation of leptonic decay products are discussed. The results are
interpreted in the context of models containing new gauge bosons (dark
photons or dark Z bosons) that give rise to lepton-jets or to more general
displaced leptonic signatures, as well as models with a high-mass,
right-handed neutrino that could be a viable dark matter candidate.
The total decay width of the Higgs boson has not yet been constrained precisely with the LHC data. Some of the width could be associated to decays to invisible particles, for example Dark Matter particles. A search for invisible decays of the Higgs boson is performed using about 10 fb-1 of p-p collisions at 13 TeV.
Determinations of the magnitude of the CKM element $|V_{ub}|$ by exclusive and inclusive decays are currently at odds by about three standard deviations. In this talk we report new and updated results on charmless semileptonic $B$ decays, based on the large data sample accumulated by the Belle experiment at the KEKB asymmetric-energy $e^+ e^-$ collider at KEK, Japan, which might help to clarify the experimental situation.
We also report the first absolute measurement of ${\cal B}(B_s \to D_s X)$ via tagging at the $\Upsilon(10860)$ resonance at Belle. The tagging of $B_s^{(*)} B_s^{(*)}$ events is obtained through reconstruction of semileptonic $B_s \to D_s X \ell \nu$ events. Previous measurements of this branching fraction are limited by model-dependence or large statistical uncertainties; a model-independent measurement enables improvements to the precision of the fraction $f_s$ of $B_s$ events at the $\Upsilon(10860)$ and anchors branching fractions of other $B_s$ decays.
We present the measurements of forward-backward charge asymmetry $A_{FB} $ in
$p\bar{p}\rightarrow Z/\gamma^{*} \rightarrow e^+ e^-/\mu^+\mu^- + X$ events
using $\sim 10\ $fb$^{-1}$ of $ p\bar p$ data collected at $\sqrt s=1.96\ $TeV by the D0
and CDF detectors at the Fermilab Tevatron collider. $A_{FB}$ is measured as a function
of the invariant mass of the dilepton system to extract the effective weak mixing angle $\sin^2\theta^{lep}_{eff}$.
In the context of the standard model, using the on-shell renormalization scheme where
$\sin^2\theta_W = 1 - M_W^2/M_Z^2$, measurements of $\sin^2\theta^{lep}_{eff}$
yield indirect extractions of the W mass. We discuss the recent measurement of $\sin^2\theta^{lep}_{eff}$
using di-muon events at D0 and its combination with the di-electron channel [ PRL 115, 041801 (2015)].
We also present the CDF-legacy measurement of $\sin^2\theta^{lep}_{eff}$ using electron pairs
and its combination with the previous CDF-legacy measurement using muon pairs [PRD 89, 072005 (2014)].
We also present the combination of the D0 and CDF results.
Publicly funded science requires a public that values research. Physicists with expertise in public outreach will have small informal discussions with groups of people interested in learning how to engage the public.
Beyond the standard model theories like composite Higgs models predict resonances with large branching fractions in a Higgs boson and a vector boson with negligible branching fractions to light fermions. We present an overview of searches for new physics containing a Higgs boson and a W or Z boson in the final state, using proton-proton collision data collected with the CMS detector at the CERN LHC. For high-mass resonances decaying to intermediate bosons, the large boost for hadronic decays gives rise to one single "merged'' jet, which can be identified through a study of its substructure consistent with the presence of two quarks, enhancing the sensitivity due to the large branching ratios for hadronic decays. B-quark identification algorithms are used in addition to identify the hadronic H decays.
Many extensions to the Standard Model predicts new particles decaying
into two massive vector bosons (WW, WZ, ZZ making this a smoking gun
signature. Searches for such diboson resonances have been performed in
final states with different numbers of leptons and jets where new jet
substructure techniques to disentangle the hadronic decay products in
highly boosted configuration are being used. This talk summaries ATLAS
searches for diboson resonances with LHC Run 2 data.
SPIDER is a powerful balloon-borne instrument to map the polarization of the cosmic microwave background (CMB) at large angular scales. SPIDER targets the B-mode signature of primordial gravitational waves, with a focus on mapping a large sky area with high fidelity at multiple frequencies. SPIDER’s six monochromatic refracting telescopes (three each at 95 and 150 GHz) feed a total of more than 2000 antenna-coupled superconducting transition-edge sensors. A sapphire half-wave plate at the aperture of each telescope modulates sky polarization for control of systematics. I will discuss SPIDER’s first long-duration balloon flight in January 2015, including performance estimates and the current status of data analysis. I will also give an update on development toward SPIDER's second flight, which will feature expanded frequency coverage.
The BICEP/Keck Array program comprises a series of telescopes at the South Pole designed to measure cosmic microwave background polarization at degree angular scales, in search of imprints of inflation. This talk will describe the latest science results and recent technical improvements enabling further growth of the program. We use BICEP2 and Keck Array data collected through 2014 in 150GHz and 95GHz bands, in combination with Planck and WMAP data to constrain a model consisting of lensed-LCDM, galactic dust and synchrotron emission, and an inflationary gravitational wave (IGW) component. An excess over lensed-LCDM is detected and is consistent with dust. No significant evidence is found for synchrotron emission. We set a 95% confidence upper limit on inflationary tensor-to-scalar ratio, r<0.09 (0.07 when combined with Planck and WMAP data). This represents the first time that limits on inflationary tensors from CMB polarization have surpassed the constraining power of CMB temperature data alone. Data acquired in the 2015 season includes that from two new 220 GHz receivers deployed in the Keck Array to enhance sensitivity to dust emission. An additional two 220 GHz receivers were fielded in January 2016. We have also developed and deployed BICEP3, a 95 GHz receiver with 10x throughput compared to BICEP2. The high-throughput design of BICEP3-class receivers will be replicated to field an array replacing the current BICEP2-class receivers in the Keck Array. The resulting experiment called BICEP Array will hold ~30,000 detectors spanning five frequency bands from 35 GHz through 270 GHz, and will perform a deep search for IGW in the presence of galactic emission and lensing foregrounds.
I present the first results from three-flavor lattice QCD for the hadronic matrix elements for neutral $B_{(s)}$-meson mixing in and beyond the Standard Model, including a complete error budget for each matrix element. Because $B_{(s)}$-meson mixing proceeds via flavor-changing neutral currents, it is potentially sensitive to new physics. We compute the complete basis of matrix elements, at leading order in the electroweak operator product expansion, needed to make predictions in the Standard Model and beyond. From our matrix element results we derive a host of phenomenologically interesting quantities, including the most precise determination to date of the CKM matrix elements $|V_{td}|$, $|V_{ts}|$, and their ratio $|V_{td}/V_{ts}|$, as well as Standard Model predictions for $B_{(s)}-\bar B_{(s)}$ oscillation frequencies and the rare decay branching fractions $\mathcal B(B_{(s)} \to \mu\bar\mu)$. I will discuss several 2 to 3 standard deviation tensions between Nature and the Standard Model expectations based on our results.
New lattice QCD results from the RBC-UKQCD collaboration have opened the door for a reliable
theory analysis of $\epsilon_K^\prime$, which quantifies direct CP violation
in $K\to \pi\pi$ decays. The Standard-Model (SM) prediction disagrees with
the measurement by 2.9 standard deviations. While in most models of new
physics the data on indirect CP violation (characterized by the
well-understood quantity $\epsilon_K$) preclude sizable effects in
$\epsilon_K^\prime$, large effects are possible in the Minimal
Supersymmetric Standard Model.
We calculate fluctuations and correlations of conserved charges
in finite temperature QCD up to sixth order. These are interesting
for their sensitivity to criticality, for probing the relevant
degrees of freedom in the QCD medium, for providing stringent
tests on the hadron resonance gas model at low and resummed
perturbation theory at high temperatures, and for being accessible
to heavy ion collider experiments. They can also be used for
the extrapolation of physical quantities to small finite chemical
potentials. Our simulations use staggered quarks with physical
quark masses. All of our results are extrapolated to the continuum limit.
Run 2 of the LHC offers unparallelled potential to discover new physics (NP).
As NP is often considered to couple to the strong force, jet based searches
provide exciting opportunities. The latest ATLAS and CMS search results in inclusive
and heavy-flavour high transverse momentum jet searches will be presented.
A search is conducted for both resonant, and non-resonant new phenomena in
the dilepton final state, using the ATLAS experimental data. Resonance
interpretations are given for a Z' or Graviton, while Contact Interactions
are considered for the non-resonant interpretation, with the dilepton
invariant mass used as the discrimination variable throughout. The full LHC
2015 proton-proton dataset is combined with the data which has been
collected so far during 2016, at sqrt(s) = 13 TeV.
We present searches for vector-like quarks that only couple to light generation quarks, in LHC proton-proton collisions using the CMS experiment. Vector-like quarks are generally considered to mix significantly only with quarks of the third generation. However, cancellations among different vector-like quark contributions can relax constraints on mixing with lighter generations, leaving room for new quarks with sizable couplings to the light quarks. The heavy vector-like quarks can decay to a W, Z or H boson and a quark of the first generation. We use two approaches: an inclusive search for single and pair production, and an exclusive search for pair production with kinematic fit to exclusive channels. Final states with at least one muon or one electron are considered. Results are combined for single and pair production processes.
New quarks appear in many beyond the Standard Model trying to cancel the
mass divergence for the Higgs boson. The current status of the ATLAS
searches for single production of such news quarks will be reviewed,
addressing the used analysis techniques, in particular the selection
criteria, the background modelling and the related experimental
uncertainties. The phenomenological implications of the obtained results
will also be discussed.
Semileptonic decays of B-mesons into excited charmed mesons of the 1P quadruplet are investigated in the context of the Standard Model and the type II two-Higgs doublet model. Predictions for differential branching fractions as a function of the four-momentum transfer squared are presented for the charmed meson either being a D2, D1, D1' or D0-meson, as well as predictions for the ratios of the semi-tauonic and light lepton semileptonic branching fractions. These predictions rely on the determination of the leading Isgur-Wise function from the measured total branching fraction of the narrow 1P states and hadronic branching fractions which are connected through a factorization theorem to the semileptonic form factors at maximal recoil of the initial B-meson and excited charmed mesons. In addition, the dependence of the ratio of semi-tauonic and light lepton branching fractions on the MSSM parameters tanβ and mH+ is predicted for all states of the quadruplet.
In this talk, we present studies of $\tau$ leptons at Belle and the prospects at SuperKEKB/Belle II.
We evaluate the Michel parameters of $\tau$ leptonic decay using Belle’s full data sample. This measurement is important to reveal the Lorentz structure of $\tau$ leptonic decay, which includes not only the $V-A$ interaction but also contributions from scalar, tensor and others that may arise from New Physics; this measurement tests lepton universality as well. We also measure branching fractions of $\tau$ decays into three charged pseudo-scalars and a tau neutrino using the full sample of Belle. In the previous analysis by Belle, some deviation from the existing measurements was seen for the branching fraction on $\tau \to \pi\pi\pi\nu$ mode; we expect to make this clear by our full analysis.
The Belle~II experiment aims to record 50 ab$^{-1}$ of data at the SuperKEKB energy-asymmetric $e^+e^-$ collider. The anticipated high statistics data sample has excellent sensitivity to lepton flavor violating (LFV) $\tau$ lepton decays including $\tau \to \mu \gamma$, $\tau \to \mu \pi^0/\eta$ and so on. Prospects and sensitivities for $\tau$ LFV at Belle~II will be presented.
Text coming
Text coming
Several theories beyond the Standard Model, like the 2HDM, predict the existence of high mass charged Higgs particles. Such charged Higgses, produced in association with a top quark, are searched for in the tau + jets decay channel and in the top-bottom decay channel, using about 10 fb-1 of p-p collisions at 13 TeV.
Now that the Higgs boson has finally been detected, its mass suggests that we are in a region of "metastability", with various claims being made about the lifetime of the vacuum. However, the new minimum lies in a Planckian regime, and we would expect gravity to be relevant in any decay process. The decay of a false vacuum is always described by a tunneling process, the Coleman-de Luccia instanton, however, this assumes our universe is featureless. Just as impurities can act as nucleation sites of a phase transition, gravitational impurities, in the guise of black holes, can act as bubble nucleation sites for false vacuum decay. I will describe how a black hole can significantly enhance the probability of vacuum decay, and discuss implications for the Higgs vacuum.
With its ambitious scientific programme to discover new physics, CERN has to continuously innovate to push the boundaries of technology and achieve ever higher levels of energy and luminosity in the Large Hadron Collider and to detect and process intelligently collisions of interest which occur in the LHC experiments.
Equally ambitious is CERN’s approach to transferring those technologies to society for applications beyond high energy physics, where the primary driver is to maximize dissemination and impact. This approach of putting society first, has deep implications on our dissemination strategy: favouring open dissemination models, addressing the entire business spectrum from fledgling start-up to established and mature companies, and ensuring that CERN has both a global and a local impact within its member states.
This presentation will cover how CERN maximizes dissemination, illustrated with examples from each of its main technology pillars (Detectors, Accelerators and Computing) and their journey from birth to application in industry, as well as what’s in it for industry to work with CERN and the opportunities in particular for ambitious entrepreneurs to start their company on the basis of CERN technology.
As part of the Fraunhofer-Society, Fraunhofer Institute for Reliability and Microintegration (IZM) specializes in applied and industrial contract research. Fraunhofer IZM’s focus is on packaging technology and the integration of multifunctional electronics into systems. Due to the knowledge in electronic packaging, system integration and reliability engineering Fraunhofer IZM has been a partner for high energy physics experiments since more than sixteen years. One main focus is the development and manufacturing of hybrid pixel detector modules. Pixel detector modules from Fraunhofer IZM are part of the vertex tracking detectors of ATLAS and CMS at the LHC at CERN as well as part of CSPADs at LCLS at SLAC. Furthermore modules were produced for many other research groups and companies from all over the world, starting from one device for first prototyping up to a low volume production of several hundred modules. With the focus on applied research and development there are different collaboration models possible. Besides short term direct contract research and development or direct manufacturing services also long term strategic alliances and cooperative projects have been started together with research groups from high energy physics experiments.
The talk will give an overview of applied research topics and opportunities for collaboration with Fraunhofer. Moreover different projects that have been started with partners from high energy physics experiments and new developments related to electronic packaging will be presented.
The Institute of Physics (IOP) has a longstanding interest in diversity issues, particularly around the participation of girls and women in physics, who are under-represented in physics education and employment. In 2003, the Institute introduced a Site Visit scheme, in which selected panels visited physics departments and produced a dedicated report on their “gender inclusiveness”. After two years, the results of these visits were condensed into a general report: Women in University Physics Departments: a Site Visit Scheme. Building upon the best practice identified in this influential report, in 2007 the IOP established Project Juno, an award scheme that aims to promote gender equality in higher education physics departments. The Juno Principles provide a framework for specific actions to improve the participation and retention, particularly of women, in physics careers. The main aims of the scheme are to develop an equitable, open and transparent working culture in which students and staff, men and women, can all achieve their full potential; to promote open discussion of gender and other equality issues; and to encourage departments to determine priorities for action. Departments submit for the award and are assessed by an independent Panel of physicists with longstanding experience of addressing gender equality issues. There are three levels of the scheme (Supporter, Practitioner and Champion) and almost all of the 55 physics departments in the UK and Ireland are now participating, together with Research Institutes and one company. Currently, there are 22 Supporters, 14 Supporters and 15 Champions.
Professional physicists are a largely homogeneous group. According to the American Institute of Physics's Statistical Research Center, only 17% of bachelor's degrees and 12% of PhDs in the US go to women; 8% of bachelors and 1% PhDs go to Hispanic, African American and Native American students. In contrast, the college age US population is 50% women and 28% Hispanic, African American and Native American, which indicates that a large fraction of potential physics talent is untapped. Myriad factors, from institutionalized racism to lack of exposure about STEM careers, contribute to this gap in participation. Closing this gap requires concerted effort on many fronts. This abstract focuses on one such front: providing access to quality research opportunities for students from under represented groups through a summer research program through the Nuclear and Particle Physics Consortium at the California State University (CSU) system.
With 23 campuses serving over 450,000 students from a diverse range of backgrounds, the CSU system is the largest public university system in the United states. It is also a minority serving institution. In 2013, the student body was 41% Latino (32% Mexican American) and 5% African American. At least 35% are the first person in their family to attend college. However, the campuses have limited research opportunities for students. We will discuss a program started by Professor Yongsheng Gao of CSU Fresno, and supported by the NSF International Research Experiences for Students and several CSU campuses, to provide CSU students with summer research experiences at CERN with mentors from a variety of institutions. Students are prepared for the program by taking an online course on particle physics taught by Professor Gao, and doing several months of practical tutorials with CSU Fresno and Stanford University students and postdocs. Our talk will focus on the preparation and experiences of both the student and mentors.
Numerous surveys of modern particle physics indicate that the discipline is still largely a male pursuit, and one in which women and other marginalised groups continue to face discriminatory practices. The fraction of female particle physicists reduces with each career stage. Early career particle physicists face precarious employment conditions with serial short term contracts, long working hours, the frequent need to relocate, and little prospect for a permanent academic position. There are indications that these employment conditions add to the gender-imbalance in the field, but clearly, this problem directly affects both male and female early career scientists. The LHCb experiment has, as the first (and so far only) LHC experiment, created a dedicated office for Early Career Gender and Diversity (ECGD) (see http://lhcb.web.cern.ch/lhcb/ECGD_Office/ECGD-intro.html ). The ECGD office’s role is to to advise the management on ECGD matters; provide a point of contact for anybody experiencing any kind discrimination, bullying or harassment; collate regular statistics and other relevant information related to gender and, where appropriate, other ECGD matters; organise regular open meetings where ECGD matters are discussed. We report on our first year of experiences as the first ECGD officers in the LHC’s first ECGD office. Amongst the pitfalls of such an office is the potential of being perceived as either inconsequential, or as an external body that is a source of new rules and complications. We will highlight the strategies we adopted in an attempt to circumnavigate these pitfalls, aiming to be (and be seen as) an integral part of LHCb, working with the entire collaboration to achieve an environment in which all members can thrive. We will also discuss a few highlights of our programme in that year, including well-attended plenary meetings at LHCb weeks on topics such as “mentoring”, “(m/p)aternity leave”, “sexual harrassment”, “careers inside and outside HEP” - and the implementation of a mentoring scheme.
The technology, methods and data processing algorithms developed for experiments in high energy physics are often considered by public opinion as being far from real-life applicability. Actually many particular technologies can find their applications outside of HEP presenting significant commercialization potential. This contribution is focused on applications of digital particle counting and tracking detectors and measurement methods enabled by them. The detectors were developed by the CERN-based Medipix collaborations, implementing know-how from HEP but adapting it also for applications beyond fundamental research.
The commercialization of such advanced technology faces significant challenges since a real market outside science does not yet exist. The potential commercial users are not informed about the availability of these technologies and their capabilities. On the other hand scientists are not fully knowledgable about the real challenges and needs in industry. For instance, some modern composite materials require novel inspection techniques, which are not available with existing technologies. The same is true for modern medical therapeutic and diagnostic methods. High performance imaging instrumentation based on particle tracking detectors allows, in many cases, to bring accelerator based techniques to common laboratories or even construct a portable solution.
Several examples of commercial applicability of such instrumentation in the field of radiation imaging in industry, medicine and other fields will be described. They include advanced spectroscopic imaging methods (mostly with X-rays: imaging based on absorption, scattering or phase effects) for non-destructive testing and analytical imaging as well as applications of particle tracking based imaging.
Micro-Pattern Gaseous Detectors (MPGDs) are devices often used for charge particle tracking, as exemplified at the LHC experiments. These devices were introduced to improve the position resolution, the capability to cope with high particle flux, and the long term stability compared to the Multi-Wire Proportional Chambers. In recent years, MPGDs found applications beyond high energy physics mainly due to their imaging capabilities and the advantageous size over price ratio. Some examples that do not exhaust the list of applications are:
The developments to obtain a radiation-hard detector based on Gaseous Electron Multipliers (GEMs) for imaging and dosimetry during gamma-ray treatments.
GEMs have been used for X-ray fluorescence of artworks in order to unveil underlying paintings over large surfaces.
A portable and battery-driven muon telescope based on Micro-Mesh Gaseous Structures (Micromegas) is used for cosmic muon tomography, presently scanning the Egyptian Pyramids.
The goal of all MPGDs is to amplify the otherwise small amount of ionisation charge produced in the gas by the interacting particles. Typically, this charge is read out electronically with an amplification and digitisation chain dedicated to each channel. An alternative is to exploit the copious scintillation of certain gases. The first ideas of taking pictures of scintillating gases go back to the beginning of the '80, and recently its potential was re-discovered. Modern MPGDs coupled to modern cameras are versatile and intuitive tools to deliver fast and good quality images. The robustness and the simplicity of this readout technique are key features which may simplify the spread of MPGDs beyond high energy physics environment. Applications range from low-energy X-ray radiography and fluoroscopy, position- and energy-resolved X-ray detection, X-ray crystallography over large areas, online beam monitor in hadron therapy treatments, and possibly several others.
A cornerstone of good scientific practice is to make results available to the public. This is especially true for experiments at the LHC at CERN where public investment in fundamental research is significant and long-standing. As part of their commitment to open access and public engagement the ATLAS and CMS collaborations have made several large datasets available to the public.
There are many challenges posed in presenting complex and high-level data to the public in an accessible and meaningful way. We describe the solutions to these challenges, part of which is the creation and use of the CERN Open Data Portal and the content found therein. Furthermore we describe the impact and future plans of the ATLAS and CMS open access efforts including future releases of data and accompanying educational material.
Fermilab Artist-in-Resident Lindsay Olson and Art@CERN director Monica Bello will discuss how the arts can enrich outreach for High Energy Physics. Using visual arts, dance, music and sound installations, the arts create an exciting and beautiful platform to educate people in ways words alone cannot. Hear about how successful arts/science collaborations make a difference in informing the public about particle physics research.
This talk reports the first measurement using the NOvA detectors of
$\nu_{\mu}$ disappearance in a $\nu_{\mu}$ beam. Oscillation parameters
$\Delta m_{32}^{2}$ and $\sin^{2}\theta_{23}$ are measured as function
of the count and energy spectrum of $\nu_{\mu}$ interactions at a
Near and Far Detector, separated by a distance of $810\text{ km}$.
High-statistics Near Detector energy spectra are compared to Monte
Carlo predictions, and discrepancies used to perform a data-driven,
bin-by-bin ``Far/Near extrapolation'' correction to the predicted
Far Detector energy spectrum. The corrected spectrum is fit to data
in $\Delta m_{32}^{2}$ and $\sin^{2}\theta_{23}$, marginalizing
over systematic uncertainties and the remaining oscillation parameters
(excepting $\delta_{CP}$, which is left unconstrained) to produce
best fit points and $90\%$ confidence level contours. Systematic
uncertainties considered cover particle simulation, cross-sections,
detector calibration, and differences in exposure and performance
between the Far and Near Detectors. This analysis uses a 14 kton-equivalent
exposure of $2.74\times10^{20}$ protons-on-target from the Fermilab
NuMI beam. Assuming the normal neutrino mass hierarchy, we measure
$\Delta m_{32}^{2}=(2.5_{-0.18}^{+0.20})\times10^{-3}\text{ eV}^{2}$
and $\sin^{2}\theta_{23}$ in the range $0.38-0.65$, both at the
$68\%$ confidence level, with two statistically-degenerate best fit
points at $\sin^{2}\theta_{23}=0.43$ and $0.60$. Results for the
inverted mass hierarchy are also presented.
NOvA is a long-baseline accelerator-based neutrino oscillation experiment that is optimized for NuE measurements. It uses the upgraded NuMI beam from Fermilab and measures electron-neutrino appearance and muon-neutrino disappearance at its Far Detector in Ash River, Minnesota. The NuE appearance analysis at NOvA aims to resolve the neutrino mass hierarchy problem and to constrain the CP-violating phase. The first measurement of electron-neutrino appearance in NOvA based on its first year’s data was produced in 2015, providing solid evidence of NuE oscillation with the NuMI beam line and some hints on mass-hierarchy and CP. This talk will discuss the second NuE oscillation analysis at NOvA, which is based on 2 years of data.
Merging the following abstracts:
The T2K long-baseline neutrino oscillation experiment has been running in anti-neutrino mode since 2014 and recently released anti-neutrino oscillation results. These results have been updated with further data and now include the full three-flavour anti-neutrino oscillation analysis. We will present these new results and compare them with the neutrino oscillation results, giving the most sensitive comparison to date. The three-flavour neutrino and anti-neutrino results are used to obtain world-leading measurements of δCP, θ23 and Δm223.
The T2K long-baseline neutrino experiment is in the process of proposing a follow-up experiment, T2K2, with higher beam intensity, upgraded detectors and improved sensitivity to neutrino properties. The anticipated sensitivity and reach of T2K2 will be discussed in this talk, as well as possible detector upgrades. In particular, the sensitivity should allow for a 3σ discovery of CP violation in the case of maximum CP violation, after 10 years of data-taking.
Text coming
We present a search for new massive particles decaying to heavy-flavour quarks with the CMS detector at the LHC. Decay channels to vector-like top partner quarks, such as T', are also considered. This results in a top-pair-like final state, as the T' decays to a W boson and bottom quark; however the reconstructed mass of the T' can be used to further signal discrimination. We use proton-proton collision data recorded at a centre-of-mass energy of 13 TeV. The search is performed in both hadronic and semileptonic decay channels of the top quark or of the top-partners. Due to the high momentum range in which these objects are produced, specific reconstruction algorithm and selections are employed to address the identification of these boosted signatures.The results are presented in terms of upper limits on the model cross section.
A search for new resonances that decay into top quark pairs and new
resonances that decay into a top quark and a b quark are reported. The
search is performed with the ATLAS experiment at the LHC using
proton-proton collision data collected at a centre-of-mass energy of
$\sqrt{s}=13$ TeV. Both the lepton plus jets channel in the top pair
search and the all hadronic channel are explored in both searches. In the
top pair search, the invariant mass spectrum of top quark pairs is examined
for local excesses or deficits that are inconsistent with the Standard
Model prediction. In the top-bottom search, the invariant mass spectrum of
the $tb$ final state is reconstructed and compared to the Standard Model
prediction.
Many models of physics beyond the standard model predict events that
contain two or more leptons with or without extra jets, missing energy,
accompanying b-quarks, etc. This talk highlights ATLAS searches targeting
new heavy neutrinos and leptons and multicharge Higgs-like particles in
multilepton final states with the first LHC Run2 Data.
Fermion compositeness would give rise to excited states of quarks and leptons. Such states would radiatively decay to standard-model fermions. This talk present searches for such decays, focusing on the recent results obtained using data collected at Run-II of the LHC.
We present the results of measurement of electroweak penguin B decays. We show the full angular analysis of $B \to K^* \ell^+ \ell^-$ to extract form factor insensitive variables such as $P'_5$. The branching fraction of inclusive $b \to s \ell^+ \ell^-$ is measured with a sum-of-exclusive-modes approach. We also report searches for leptonic $B$ decays including the lepton-flavor-violating mode: $B \to e^+e^-$, $\mu^+\mu^-$, $\tau^+\tau^-$, $e^\pm \mu^\mp$. All the analyses are based on the full data set of Belle containing 772 million $B\overline{B}$ pairs.
A related decay $B_s \to \tau^+\tau^-$ can also be studied by a hadronic $B_s$ tagging tool that is being developed for the data sample of 121${\rm fb}^{-1}$ collected at the $\Upsilon(10860)$ resonance at Belle. The method is based on a hierarchical approach in which the $B_s $ mesons and their daughters are reconstructed in several stages, harnessing more than 100 neural network variables.
A precise O(10 MeV) measurement of the W boson mass is a stringent test of the standard model. The talk will discuss the experimental and theoretical challenges that need to be faced in order to achieve this level of precision. In addition, the status of various experimental studies, calibrations and state-of-the-art simulations related with this measurement will be presented.
High luminosity operation of the LHC is expected to deliver proton-proton collisions to experiments with average number of pp interactions reaching 200 every bunch crossing. Reconstruction of charged particle tracks with current algorithms, in this environment, dominates reconstruction time and is increasingly computationally challenging.
We discuss the importance of taking computing costs into account as a critical part of future tracker designs in HEP as well as the importance of algorithms used.
Hot topics on the table for discussion with our Panel! Comes with questions and ideas!!
Text coming
Results of searches for long-lived particles that decay to either pairs of
hadronic jets or clusters of variously displaced hadronic vertices
(emerging jets) in proton-proton collisions with the ATLAS detector at a
center-of-mass energy of 13 TeV are presented. The results are interpreted
in the context of several models, including hidden valleys with high-mass
scalars, baryogenesis models, stealth SUSY, and models with QCD-like dark
hadronization.
Numerous new physics models, e.g., theories with extra dimensions and various gauge-group extensions of the standard model, predict the existence of heavy resonances decaying to final states containing leptons. This talk presents searches for new physics in the dilepton, lepton+MET, and Z(ll)gamma final states at CMS, focusing on the recent results obtained using data collected during the 2015 run as well as the first part of the 2016 run.
Results of searches for particles with anomalously high or fractional
electric charge produced in proton-proton collisions in the ATLAS detector
at a center-of-mass energy of 13 TeV are presented. Such signatures,
encompassing particles with charges from 2 to 60 times the electron charge,
involve high levels of ionization in the ATLAS detector and can arise from
magnetic monopoles or models involving technicolor, doubly charged Higgs
bosons or composite dark matter models.
Several supersymmetric models predict massive long-lived supersymmetric particles with lifetimes from fractions of a nanosecond to lifetimes that are effectively stable in the detector. Such particles may be detected through abnormal specific energy loss, disappearing tracks, displaced vertices, long time-of-flight or late calorimetric energy deposits. The talk presents recent results from searches for long-lived supersymmetric particles with the ATLAS detector. The increase in the center-of-mass energy of the proton-proton collisions gives a unique opportunity to extend the sensitivity to production of supersymmetric particles at the Large Hadron Collider. Results will be based on pp collisions at sqrt(s) = 13 TeV.
Measurements of the top quark mass are presented using data collected by the CMS experiment in proton-proton collisions at the LHC at centre-of-mass energies of 7 and 8 TeV. Analyses in several decay channels of top quark pair events are employed to determine the top quark mass. The results are combined and compared to the world average.
Measurements of the top quark mass employing alternative methods are presented using data collected by the CMS experiment in proton-proton collisions at the LHC in the years 2011 and 2012 at centre-of-mass energies of 7 and 8 !TeV. The alternative methods include the reconstructed invariant mass distribution of the top quark, an analysis of endpoint spectra, measurements from shapes of top quark decay distributions, as well as a measurement using leptonic top quark decays with a J/psi. The dependence of the mass measurement on the kinematic phase space is investigated. Measurements of the difference between the masses of top and anti-top quarks are also presented. Furthermore, the top quark mass, and also alpha_s are extracted from the measured top quark pair cross section.
Belle II, as the upgrade of Belle, is aiming at searching for New Physics with 40 times higher luminosity. In order to cope with such a high luminosity, pure CsI scintillation crystals whose scintillation time is around 30 nanoseconds have been proposed. And silicon avalanche photodiodes, making up for the low light yield of pure CsI, are considered as photosensors. The application of the innovative WLS which perfectly matches the emission spectrum of pure CsI and quantum efficiency of APD, maximizes the light collection. With the help of cosmic rays, the equivalent noise energy of the counter is measured.
The JUNO (Jiangmen Underground Neutrino Observatory) experiment is under preparation in China by the international collaboration. The main goal of the project is to determine the neutrino mass hierarchy by precise measurement of the energy spectrum of the antineutrinos from the nuclear reactors with help of the 20 kt liquid scintillator underground detector located at a distance of 53 km. Data taking should begin in 2020.
Performance of the JUNO experiment is related to its capability to suppress or at least to control the background processes, which may have the same signature as the antineutrino signal. There are several sources of the background but most dangerous is due to cosmogenic isotopes produced in nuclear spallation processes in cosmic muons interactions.
The Veto system of the JUNO detector is used for muon detection, muon induced background study and its reduction. It consists of the Top Tracker system and the Water Cherenkov detector. The Water Cherenkov detector is a pool filled with purified water and instrumented with PMTs surrounding the central antineutrino detector. The Top Tracker made of scintillating strips and covering ∼1/3 of the top area with 3 layers has to reconstruct the cosmic muons’ direction. This independent muon information will help muon tagging, track reconstruction and efficiency study to understand and reduce cosmogenic backgrounds.
Effect of cosmic muons, cosmogenic isotopes, spallation neutrons, and natural radioactivity as well as the design of the Veto system detectors, their performances and the strategy for the background reduction are presented.
The Dark Energy Survey (DES) Collaboration is an international
astronomy collaboration of 400 scientists (graduate student to professor) from ~30 institutions. Our public outreach and professional development programs are unique grass-roots efforts that set new standards for large science collaborations. We describe several
programs in which scientists build networks of internal support, develop connections with local communities, and reach global audiences. We prioritize professional development, diversity and inclusivity, and normalizing science in broad social contexts.
With many current and future neutrino experiments relying on Liquid Argon Time Projection Chamber (LArTPC) technology, characterizing the performance of these detectors is critical. The MicroBooNE LArTPC experiment is capable of performing
numerous measurements to better understand the technology. These include measurements of the levels of electronegative contamination using cosmic rays and purity monitors as well as electron diffusion and recombination. MicroBooNE, residing on the surface, can also provide useful information about cosmic ray rate and the build up of space charge in the TPC volume. A laser calibration system has been designed and employed to investigate these important effects.
MicroBooNE is a Liquid Argon Time Projection Chamber (LArTPC)
located in the Booster Neutrino Beam (BNB) at Fermi National Accelerator
Laboratory. This poster presents a study on charged particle multiplicity
(CPM) analysis based on a small sample of automatically and visually
identified neutrino events in the MicroBooNE detector. Initial comparison
of multiplicity distributions for data, BNB plus cosmic Monte Carlo (MC),
and true MC is presented here. Comparison of multiplicity distributions of
uncorrected data and MC show consistency. Multiplicity distributions of
corrected scanned and true MC are also in agreement. Fully automated
reconstruction will be used to proceed with this analysis with the goal of
testing models of neutrino scattering on argon such as those embedded in
GENIE and other event generators.
NOvA, a long-baseline neutrino oscillation experiment at Fermilab, is designed to
measure electron-neutrino appearance and muon-neutrino disappearance in the NuMI beam. NOvA comprises of two finely segmented liquid scintillator detectors at 14 mrad off-axis in the
NuMI beam. An accurate prediction of the neutrino flux is needed for precision oscillation and cross-section measurements. Data from the hadro-production experiments and, importantly, from the NOvA Near Detector provide powerful constraints on the muon-neutrino
and electron-neutrino fluxes. In particular, the measurement of the neutrino-electron elastic scattering provides an in situ constraint on the absolute flux. This talk presents the data-driven predictions of the NOvA muon-neutrino and electron-neutrino flux, and outlines future improvements in the flux determination.
BaF$_2$ calorimeters are radiation-hard and have good energy resolution, but the time resolution can be a problem at high rate. Indeed, the scintillation light has both a fast (decay time 0.9 ns at 220 nm) and a larger, slow (decay time 650 ns at 300 nm) component. The slow component can worsen the excellent time resolution available from the fast component.
In order to take advantage of the very fast scintillation component, it is necessary to have a
fast photosensor with high efficiency in the UV-region that is also
able to discriminate against the slow scintillation component.
A Caltech/JPL/RMD consortium has been formed to develop a modified
RMD large area APD into a delta-doped superlattice APD.
This device incorporates an atomic layer deposition antireflection
filter that will provide 60 % quantum efficiency at 220 nm
and 0.1 % efficiency at 300 nm to take full advantage
of the fast decay time component of BaF$_2$ while suppressing the slow one.
To cope with the higher rate expected for the Mu2e experiment upgrade and to reject pileup events,
This sensor will make possible to build a radiation-hard and extremely
fast BaF$_2$ based calorimeter having good energy and time resolution
and an extreme high rate capability that can cope with the
increased rates expected at upgrades for Mu2e or other experiments
with similar demands.
SBND (Short-Baseline Near Detector) will be a 112 ton liquid argon TPC neutrino detector located 110m from the target of the Fermilab Booster Neutrino Beam. SBND, together with the MicroBooNE and ICARUS-T600 detectors at 470m and 600m, respectively, make up the Fermilab Short-Baseline Neutrino (SBN) Program. SBN will search for new physics in the neutrino sector by testing the sterile neutrino hypothesis in the 1 $eV^2$ mass-squared region with unrivaled sensitivity. The SBND plays an important role in an on-going R&D effort within neutrino physics to develop the LArTPC technology toward many-kiloton-scale detectors for next generation long-baseline neutrino oscillation experiments. In this poster the development of the SBND detector will be presented.
The study of electroweak boson production is an important part of
characterizing the standard model and it can also shed a light on new
physics, in the form of anomalous gauge couplings. We present studies
based on the measurement of WW scattering, the electroweak production
of Z gamma + 2 jets and the study of gamma gamma->WW through the
exclusive WW production performed by the CMS collaboration using 8TeV
proton-proton collisions at the LHC. With this set of analyses CMS
has set upper limits on the values of aQGC coefficients for both
dimension-6 and dimension-8 effective field theory operators, with
exclusive gamma gamma -> WW giving the most stringent limits to date.
There is a significant interest in achieving high-average power electron sources particularly in the area of electron sources integrated with Superconducting Radio Frequency (SRF) systems. For these systems, the electron gun and cathode parts are critical components for stable intensity and high-average powers. In this study, we will present the design of 8.5-cell accelerator cavity having 1.3-GHz frequency and field optimization studies by using simulation results of SUPERFISH and Spiffe.
Future energy-frontier electron-positron colliders will be capable of high-precision studies of the properties of the top quark. The measurement of the top-pair production cross section around the threshold provides access to the mass of the top quark in theoretically well-defined schemes, with statistical uncertainties of 20 MeV or less, depending on the assumed integrated luminosity of the measurement. At this level of precision, experimental and theory systematics are likely to become important or even dominant. We will present a first analysis of the impact of the remaining uncertainties of the recently completed calculation of the top pair production cross section at NNNLO QCD including the exchange of Higgs bosons on the extraction of the top quark mass from a threshold scan. The analysis is based on reconstruction efficiencies and background levels obtained in full simulation studies for CLIC, combined with signal cross sections from the higher-order calculations. To assess possible differences between different collider options, the study is performed in the context of CLIC, ILC and FCC-ee, taking into account also the different projected integrated luminosities to be collected at the different colliders.
We present a measurement of the production cross-section of charm mesons in proton-antiproton collisions at 1.96 TeV center-of-mass energy, using the full data set collected by the CDF experiment at the Tevatron collider in Run II. The measurement probes a yet unexplored low transverse-momentum range, down to 1.5 GeV/c, using events selected with criteria that bias minimally the features of the collision. For initial state and collision energy, this remains a unique measurement of quantities that are important for QCD studies and for tuning Monte Carlo simulations.
Merged the following:
The NuMI Off-Axis νe Appearance (NOνA) experiment utilizes the neutrino beam produced at Fermilab, Neutrinos at the Main Injector (NuMI). The experiment consists of two detectors; the Near and Far Detectors are 810 km apart. The Near Detector, located at Fermilab, determines the initial state of the neutrino beam. In this poster, a muon neutrino selection and energy estimation are presented. Data and simulation comparisons for the Near Detector are shown.
The NuMI Off-axis electron neutrino Appearance (NOvA) can detect muon neutrinos and measure their disappearance via oscillation between the Near and Far Detectors. We will detail the latest selection methods, expected selection efficiencies, expected sample purities, and energy estimation methods for muon neutrino detection at both detectors. We will also verify all of these factors via comparison with data from the Near Detector.
Signals of QCD instanton-induced processes are searched for in
deep-inelastic scattering (DIS) at the electron-proton collider HERA in the kinematic region defined by the Bjorken-scaling variable $x> 0.001$, the inelasticity $0.2< y< 0.7$ and the photon virtuality $150< Q^2<15000$ GeV$^2$. The search is performed using H1 data corresponding to an integrated luminosity of 350 pb$^{-1}$. Several observables of the hadronic final state of the events are exploited to identify a potentially instanton-enriched domain. Two Monte Carlo models, RAPGAP and ARIADNE, are used to estimate the background from the standard DIS processes, and the instanton-induced scattering processes are modeled by the program QCDINS. In order to extract the expected signal a multivariate data analysis technique is used. Exclusion limits on instanton production are reported, excluding cross sections larger than 2 pb. Limits are also reported as a function of parameters used to regularize the perturbative instanton model.
Merged the following:
Contradictory evidence has been presented on the issue of neutrino mixing between the three known active neutrinos and light sterile neutrino species. Short-baseline neutrino oscillations observed by the LSND and MiniBooNE experiments, the collective evidence of the reactor neutrino anomaly, and the gallium anomaly all point towards sterile neutrinos with mass at the 1 eV level. While these results are tantalizing, they are not conclusive as they are in tension with null results from other short-baseline experiments, and with disappearance searches in long-baseline and atmospheric experiments.
Resolving the issue of the existence of light sterile neutrinos has profound implications for both particle physics and cosmology. The NOvA (NuMI Off-Axis νe Appearance) experiment may help clarify the situation by searching for disappearance of active neutrinos from the NuMI (Neutrinos from the Main Injector) beam over a baseline of 810 km.
In this talk, we will describe a method of how NOvA can look for oscillations into sterile neutrinos, with focus on disappearance of neutral current (NC) neutrino events, will present preliminary results of these searches, and discuss their implications in supporting or constraining the existence of light sterile neutrinos.
Anomalous results observed by short-baseline neutrino oscillation experiments LSND and MiniBooNE, the reactor neutrino and the gallium anomalies all point towards sterile neutrinos with a mass at the 1 eV scale. The evidence remains inconclusive due to tension between null results at short-baseline experiments and disappearance measurements at long-baselines. The NOvA (NuMI Off-Axis nu_e Appearance) long-baseline experiment offers a complementary probe of sterile neutrino mixing. The NOvA detectors have been optimized to detect electrons in order to measure electron-neutrino appearance. Extending the standard 3-neutrino framework to a 3+1 model that includes one sterile flavor and an extra mass state (v4) allows one to extend the current nu_e appearance measurement to measure NOvA's sensitivity to the extra CP-violating phases. In this talk we present NOvA's first analysis of these additional CP-violating phases and assess future discovery reach in the presence of a light sterile neutrino.
Three-flavor neutrino oscillations have successfully explained a wide range of neutrino oscillation experiment results. However, anomalous results, such as the electron-antineutrino appearance excess seen by LSND and MiniBooNE, do not fit the three-flavor paradigm and can be explained by the addition of a sterile neutrino at a larger mass scale than the existing three flavor mass states.
The NOvA experiment consists of two finely segmented, liquid scintillator detectors operating 14 mrad off-axis from the recently upgraded NuMI muon-neutrino beam. The Near Detector is located on the Fermilab campus, 1 km from the NuMI target, while the Far Detector is located at Ash River, MN, 810 km from the NuMI target. The NOvA experiment is primarily designed to measure electron-neutrino appearance at the Far Detector using the Near Detector to control systematic uncertainties; however, the Near Detector is well suited for searching for anomalous short-baseline oscillations and probing the LSND and MiniBooNE sterile neutrino allowed regions using a variety of final states. This talk will present a novel method for selecting samples with high purity at the Near Detector using convolutional neural networks. Based on this method, the sensitivity to anomalous short-baseline tau-neutrino appearance will be shown, and preliminary results of searches for anomalous electron-neutrino appearance and muon-neutrino disappearance at the NOvA Near Detector will be presented.
The Mu2e experiment will search for neutrinoless conversion of muons into electrons
In the field of an aluminum nucleus. The signature of this process is an electron with
energy nearly equal to the muon mass. Precise and robust measurement of the outgoing
electron momentum, combined with other background rejection methods, is essential to the
experiment. We rely on a low-mass straw tube tracker to achieve these goals. The tracking
system must operate in a vacuum and a 1 Tesla magnetic field. We have chosen to use about
20,000 thin-wall Mylar straws held under tension to avoid the need for supports within
the active volume. In addition to measuring distance from the wire by drift time,
subnanosecond measurement of signal propagation time will be used to measure position
along the wire. Charge will be measured using ADCs to provide particle identification
capability. In this talk we will describe details of the Mu2e tracker.
Axions are the result of a dynamic field, similar to Higgs field, invented to solve the so-called Strong CP-problem, i.e., why the electric dipole moment (EDM) of the neutron and proton has not been observed so far even though the theory of QCD requires otherwise. Axions as dark matter can be thought of as an oscillatory field interacting extremely weakly with normal matter other than gravitationally. The oscillation frequency is unknown, it can be anywhere between f = 200MHz to 200GHz and it’s expected to be a very narrow line, about df/f=10^-6. A very strong magnetic field can be used to convert part of that field into a very weak electric field oscillating at the same frequency as the axion field. In the coming years we plan to develop our experimental sensitivity to either observe or refute the axions as a viable dark matter candidate. That approach includes the development of ultra strong magnets, high quality resonators in the presence of strong B-fields, new resonator geometries, low noise cryo-amplifiers and new techniques of detecting axions. In addition, using the strong CAST LHC dipole field we will be able to search for dark matter axions in the 4 to 6 GHz range in the immediate future.
Another related subject, through the strong CP-problem, is the search for the EDM of the proton, improving the present sensitivity by more than three orders of magnitude. Usually the study of EDM involves the application of strong electric fields and neutral systems were thought to be easier to work with at first. Recently it became clear that charged particles in all-electric storage rings can be used, instead, for sensitive EDM searches by using techniques similar to the muon g-2 experiment. The high sensitivity study of the proton EDM is possible due to the high intensity polarized proton beams readily available today, making possible to reach 103 TeV in New Physics scale.
The Center for Axion and Precision Physics Research (CAPP) at IBS is establishing a state-of-the-art axion experiment in Korea to search for relic axion particles converting to microwave photons in a resonant cavity submerged in a strong magnetic field. The initial stage of building our axion experiment, CULTASK (CAPP Ultra Low Temperature Axion Search in Korea) is completed at KAIST (Korea Advanced Institute for Science and Technology) Munji Campus with successful installation of two new dilution refrigerators (one with 8T superconducting magnet) which could lower the temperature of cavities to less than 50 mK. A resonant cavity with the frequency tuning system is fabricated and the RF readout electronic chain is being set up. I will present the status and progress of CULTASK, soon to be complete with a DAQ and monitoring system, and future plans. I will also discuss the recent results from the development of high Q-factor, ultra pure Cu and Al cavities under high magnetic fields, utilizing the two refrigerators.
Neutrino physics is one of the most active fields in the modern nuclear and particle physics. All the mixing angles and mass differences are measured with the solar, the reactor, and the accelerator driven neutrino oscillation experiments. Yet, the mass of the lightest neutrino is not known and whether the neutrinos are Dirac or Majorana particles, is also not determined. Neutrino-less double beta decay experiment can answer both of the questions directly, and ultra-low backgrounds and excellent energy resolution are critical to discover this ultra rare phenomena. AMoRE experiment is a state-of-art experiment based on low temperature MMC sensor and ultra pure molybdate crystals containing highly enriched isotopes. It’s sensitivity goal is reaching 10^27 years of half-life and down to 15-40 meV neutrino mass.
The existence of sterile neutrinos is speculated in a few experiments and in a variety of theories. NEOS experiment performed at a commercial reactor made a new result in the parameter space of the sterile neutrinos. Some future perspectives for reactor neutrino experiments will be presented.
Astrophysical observations give overwhelming evidence for the existence of dark matter. The DAMA collaboration has asserted for years that they observe a dark matter-induced annual modulation signal in their NaI(Tl)-based detectors, while other direct detection dark matter experiments have seen no indications of a signal. I will describe the current status and prospect for alternative low-background NaI(Tl)-based dark matter experiments, and their proposed strategies for resolving the current stalemate in the field.
For many researchers, science is the easy part. Communicating that science to a media whose motives can seem confusing – and to a public that can seem indifferent – is more challenging. This session will provide researchers with an introduction to the multifaceted global media landscape, and how their science stories can fit into that landscape. A panel including journalists from the BBC and Washington Post and press officers from the UK and Japan will explain the different types of media outlets and what types of stories they’re looking for, will provide tips on pitching stories to different reporters with different needs, and will answer questions from the audience. Participants will leave with a handy checklist of what to expect when pitching to media.
Presenters
Feltman, Rachel (The Washington Post)
Ghosh, Pallab (British Broadcasting Corporation)
O’Connor, Terence (STFC)
Okada, Saeko (KEK)
Minimum bias and underlying event data from the LHC and Tevatron have been used to tune the PYTHIA. We tune Multiple Parton Interaction (MPI) parameters including three Lambda parameters. It is shown that these tunings describe selected distributions quite well, especially pt distribution at three collision energies, 0.9 TeV , 1.9 TeV and 7 TeV provided that charge particles with pT > 500MeV are used. Results are presented using three types of Parton Density Functions (PDFs) of proton : leading order (LO), modied leading order(LO*) and next-to-leading order (NLO). We found that all three types of PDFs can describe minimum bias and underlying event distributions equally well.
A parameter study of PYTHIA6 Multiple Parton Interaction (MPI) using best fit to the data published by ATLAS Collaboration is presented. Altogether thirteen parameters are investigated to find the most sensitive parameters to the selected data. This type of study helps in better understanding of different parameters needed to be used in PYTHIA6 tunes.
Radio detector arrays such as RICE, ANITA, ARA, and ARIANNA target the discovery of both cosmogenic neutrinos and the sources of the PeV-scale astrophysical neutrinos observed by IceCube. These radio arrays exploit the Askaryan effect and the radio transparency of glacial ice, which together enables the economical instrumentation of necessarily large volumes of ice. We describe here the electronics design of a digitally-phased radio array that would both lower the energy threshold of existing radio detectors and provide a more efficient coverage of the instrumented volume of ice.
A real-time trigger board digitizes 8 antennas each at 7-bit resolution and at a Nyquist sampling rate of 1.5 GHz.
The digital correlation between antennas in the array is performed in an on-board field-programmable gate array, which includes several gigabit serial-links to daisy chain trigger boards in order to phase larger arrays. The first implementation of this radio phased-array will be as a dynamic vertically-polarized trigger for the ARA detector at the South Pole. We will characterize the electronics in-situ and use the 16-antenna phased array as an impulsive triggering device in this initial installation planned for 2017.
B-Lab is an open data analysis program to give members of the public a taste of particle physics by presenting tools to search real experimental data for particle decays. This program started as an outreach program for Belle experiment, targeting high school students. It utilizes an adapted data sample of 1.3 /fb of the real experimental e+e- collisions accumulated at KEK by the Belle detector.
The data is provided in ROOT format, and includes the 4-vector, charge and particle identification of particles from these collisions. The analysis is done using ROOT with simple C++ source code examples, which may be adapted for the reconstruction of various combinations of particles. Students are provided with instructive examples, and then given tasks to complete using the B-Lab interface. The public use of B-Lab began in 2004, and since then, more than 1200 people have participated in the program. We report the results of the particle searches, and discuss the impacts of and potential improvements are considering for B-Lab.
We also want to introduce "BellePlus", a 4-day summer program for high school students held annually at KEK. The purpose of this workshop style program is to give an experience of researchers to students, and B-Lab is used as one of the studies in this program. We will also discuss our plans to use B-Lab as an outreach program for Belle II.
The Deep Underground Neutrino Experiment (DUNE) will search for nucleon decay as one of its primary physics goals. Understanding the processes that mimic nucleon decay is critical, as these backgrounds affect the experiment’s reach and sensitivity. The backgrounds to nucleon decay can arise from atmospheric neutrino interactions and from cosmic ray interactions that result in neutral particles entering undetected into the fiducial volume and charge exchanging or decaying to mimic nucleon decay. DUNE will be particularly sensitive to SUSY-favored nucleon decay modes that involve kaons in the final state, and therefore also to cosmogenically induced backgrounds to those modes. Progress in studies of cosmogenic backgrounds to DUNE nucleon decay searches will be presented.
Merged the following:
The observation of neutrino oscillation provides evidence of physics beyond the standard model, and the precise measurement of those oscillations remains an important goal for the field of particle physics. NOνA will soon be one of the foremost experiments in that field. Taking advantage of a tightly focused off-axis view of the NuMI neutrino beam, and a finely instrumented liquid scintillator detector, NOνA has an excellent opportunity to make high precision measurements of neutrino interactions using its Near Detector. This presentation will explain how the design of the NOνA experiment enables a wide program of neutrino interactions research, describe the broad range of cross section and final state interactions which we are able to measure, and show early results from the NOvA Near Detector.
The NOvA experiment is a long-baseline neutrino oscillation experiment designed to measure the rate of electron neutrinos appearance in a muon neutrino beam. It consists of two finely segmented, liquid scintillator detectors at 14 mrad off-axis in the NuMI beam. The NOvA Near Detector, located at Fermilab, provides an excellent opportunity to study neutrino-nucleus interactions which are important for neutrino oscillation measurements. This presentation will present one of the first such measurements from NOvA: neutrino-induced coherent-π0 production. Neutrinos can coherently interact with the target nucleus via neutral current exchange and produce a single, forward π0, which makes background to the νe appearance measurement. The analysis measures the coherent-π0 kinematics and cross-section and compares to model predictions, and also provides a data constraint on π0 production in the neutral current resonance and deep-inelastic interaction.
NOvA is a long-baseline neutrino oscillation experiment optimized to observe νμ→νe transition in the 97% pure muon-neutrino NuMI beam originating at Fermilab. It consists of two functionally identical, nearly fully-active liquid-scintillator tracking calorimeters. The Near Detector at Fermilab is located 1 km from the NuMI beam target and is used to measure the neutrino energy spectrum before standard oscillations occur. Due to its proximity to the neutrino source, the detector records neutrino interactions with high statistics. The off-axis location of the detector results in a beam neutrino energy peak close to 2 GeV, an energy regime of particular interest to neutrino cross section modeling and future neutrino oscillation experiments. In this talk, I will present the measurement of the muon-neutrino charged current inclusive cross section using the first two years of the NOvA Near Detector data.
The concept for the 10-kiloton scale Far Detector modules for the Deep Underground Neutrino Experiment (DUNE) utilizes liquid argon Time Projection Chambers (TPCs). To fully exploit the physics opportunities (measurement of CP violation in oscillations of beam neutrinos, plus non-beam based investigations including studies of supernova neutrino bursts and searches for nucleon decay), the TPC’s will be augmented with a system to detect the 128-nm scintillation photons produced in conjunction with the ionization signal. We have carried out detailed studies of the response of prototype photon detectors consisting of light guide assemblies employing wavelength shifter(s) to first convert the VUV light to wavelengths that match the silicon photomultiplier (SiPM) read out. Specifically, we report on a series of experiments conducted in a 460-liter dewar located at the liquid argon detector R&D facility at Fermilab. The large-volume setup provides an opportunity to conduct studies with multiple photon detectors in a controlled environment with filtration and purity monitoring. An external hodoscope allows for the selection of through-going cosmic muons. By simultaneous testing of prototypes of differing designs, we have measured their relative efficiencies. Additional work is underway to determine absolute efficiency. We also report the results of studies of the time-structure of the scintillation signal and detector response under varying experimental conditions.
JUNO is a Liquid Scintillator Antineutrino Detector (LAND) currently under construction in the south of China (Jiangmen city, Guangdong province). Once completed, it will be the largest LAND ever built, consisting in a 20 kt target mass made of Linear Alkyl-Benzene liquid scintillator, monitored by roughly ~18000 twenty-inch high-QE photomultipliers (PMTs) providing a ~80% photo-coverage. Large photo-coverage and large QE are two key requirements of the experiment to yield ~1200PE/MeV needed to achieve the potentially unprecedented ~3% total energy resolution at 1 MeV. This is mandatory to determine the neutrino mass ordering. In order to address the systematic uncertainty challenge causing the non-stochastic component of the energy resolution, the JUNO collaboration conceived a novel neutrino detector design comprising a second layer of small PMTs. This is geared to provide a second calorimetry handle with complementary systematic budget, allowing a combined, more precise and more accurate energy scale definition. We refer to this calorimetry redundancy system as double-calorimetry. In my talk, I will review the motivations which led us to introduce double-calorimetry in JUNO, including the trailblazing capabilities of this approach, as well as the technical challenges associated to its realisation and implementation.
After a short review on the status of QGP, we present a systematic analysis for the electromagnetic and the transport properties of this new-state-of-matter under extreme conditions of high temperature and density and finite magnetic and electric fields. The possible influences on the hadron-quark phase transition(s) and the QCD equations of state are determined from the mean field approximation of the Polyakov linear sigma model (PLSM). We also determine the electric and heat conductivity and the bulk and shear viscous properties by means of Green-Kubo correlation and Boltzmann master equation with Chapman-Enskog expansion
The Global Feature Extractor (gFEX) module is a component of the Level I trigger system for the ATLAS experiment planned for installation during the Phase I upgrade in 2018. This unique single ATCA board with multiple high speed processors on board will receive coarse-granularity information from all the ATLAS calorimeters enabling the identification in real time of large radius jets for capturing Lorentz-boosted objects such as top quarks, Higgs, Z and W bosons. The gFEX architecture is also suitable for the calculation of global event variables such as missing transverse energy, centrality for heavy ion collisions and event-by-event pile-up subtraction.
gFEX will use 3 processor Xilinx Ultra-scale FPGAs for data processing and one single system-on-chip processor, ZYNQ, for configuring all the processor FPGAs and monitoring the board status. The current pre-prototype board which includes one ZYNQ and one Vertex-7 FPGA has been designed for testing and verification. The design of the final gFEX module as well as the performance of the pre-prototype will be presented. This unique board will allow us to increase the sensitivity of the ATLAS experiment in the high luminosity environment expected during the phase I of ATLAS data taking. Although the board is being designed specifically for the ATLAS experiment, it is sufficiently generic that it could be used for fast data processing at other HEP or nuclear physics experiments.
The GlueX experiment at Jefferson Lab is a fixed target photoproduction experiment located in the newly-constructed Hall D. It is designed to study the spectroscopy of a variety of hadrons, with special emphasis on hybrid mesons. The experiment uses a 12 GeV electron beam incident on a diamond radiator to produce a linearly-polarized tagged bremsstrahlung photon beam of energies up to 12 GeV, peaking at 9 GeV. This photon beam is incident on a liquid hydrogen target surrounded by a spectrometer that combines charged particle tracking, electromagnetic calorimetry, and time-of-flight measurements . Initial commissioning data were taken at lower beam energies in the Fall of 2014 and Spring of 2015, with a final commissioning run at full energy scheduled in the Spring of 2016. Results for detector performance and preliminary results for the reconstruction of several exclusive final states will be presented.
The measurement of the differential cross-sections for a W (-> mu nu)
boson produced in association with jets is presented using 8 TeV
proton-proton collisions data recorded by the CMS detector at the LHC,
corresponds to an integrated luminosity of 19.6 fb-1. The differential
cross sections are measured as a function of jet multiplicity, the jet
pT and pseudorapidity, total hadronic activity HT for different jet
multiplicities and several angular correlation distributions among
jets and the muon. The cross section measurements are then compared
with the predictions from LO and NLO generators, and from NLO and
NNLO theoretical predictions.
We consider the measurement of the trilinear couplings
of the neutral Higgs bosons in the Minimal Supersymmetric
Standard Model (MSSM) at a high energy $e^+ e^-$ linear
collider in the light of the discovery of a Higgs
boson at the CERN Large Hadron Collider~(LHC). We identify the state
observed at the LHC with the lightest Higgs boson ($h^0$) of the MSSM,
and impose the constraints following from this identification, as well
as other experimental constraints on the MSSM parameter space. In order
to measure trilinear neutral Higgs couplings, we consider different
processes where the heavier Higgs boson ($H^0$) of the MSSM is produced
in electron-positron collisions, which subsequently decays into a pair of
lighter Higgs boson. We identify the regions of the MSSM parameter space
where it may be possible to measure the trilinear couplings of the Higgs
boson at
a future electron positron collider.
Production of top quark pairs in association with heavy Standard Model bosons or with heavy flavor quark-pairs is important both as a signal and a background in several ATLAS analyses. Strong constraints on such processes cannot at present be obtained from data, and therefore their modelling by Monte Carlo simulation as well as the associated uncertainties are important. This poster documents the Monte Carlo samples currently being used in ATLAS for the ttbarH and ttbarV (V=W,Z vector bosons) and tt+bottom and charm quark pairs processes for sqrt(s)=13
TeV proton-proton collisions.
The possible existence of sterile neutrinos is an important unresolved question for both particle physics and cosmology. Data sensitive to a sterile neutrino is coming from both particle physics experiments and from astrophysical measurements of the Cosmic Microwave Background. In this study, we address the question whether these two contrasting data sets provide complementary information about sterile neutrinos. We focus on the muon-disappearance oscillation channel, taking data from the MINOS and Planck experiments, converting the limits into particle physics and cosmological parameter spaces, to illustrate the different regions of parameter space where the data sets have the best sensitivity. For the first time, we combine the data sets into a single analysis to illustrate how the limits on the parameters of the sterile-neutrino model are strengthened. Finally, we investigate how data from future accelerator neutrino experiments will be able to further constrain this picture.
The NOvA experiment is a long-baseline neutrino oscillation experiment designed to measure the rate of electron neutrinos appearance in a muon neutrino beam. It consists of two finely segmented, liquid scintillator detectors at 14 mrad off-axis in the NuMI beam. The NOvA Near Detector, located at Fermilab, provides an excellent opportunity to study neutrino-nucleus interactions which are important for neutrino oscillation measurements. This presentation will present one of the first such measurements from NOvA: neutrino-induced coherent-$\pi^0$ production. Neutrinos can coherently interact with the target nucleus via neutral current exchange and produce a single, forward $\pi^0$, which makes background to the $\nu_e$ appearance measurement. The analysis measures the coherent-$\pi^0$ kinematics and cross-section and compares to model predictions, and also provides a data constraint on $\pi^0$ production in the neutral current resonance and deep-inelastic interaction.
We present the performance of the CMS-CASTOR forward calorimeter
during LHC Run2 data taking at a centre-of-mass energy of 13 TeV.
Results on alignment and calibration are shown, together with a
summary of produced physics output.
The MINOS experiment made precision measurements of the neutrino
oscillation parameters that are governed by the atmospheric
mass-squared splitting. These measurements were made with data that
were collected while the NuMI muon neutrino beam operated in a low
energy mode that peaks around 3 GeV. Today the NuMI beam is running
with a higher energy mode that produces a neutrino energy spectrum
that peaks around 7 GeV, allowing the MINOS+ experiment to probe
neutrino oscillation phenomena that could potentially be governed by a
fourth mass-squared splitting. If observed, the presence of a fourth
mass-squared splitting would be compelling evidence for a sterile
neutrino state. In this analysis, we will present the results of a
search for $\nu_\mu$ $\rightarrow$ $\nu_e$ oscillation mediated by
sterile neutrinos in MINOS+. The results will be contrasted against
the measurements made by the LSND experiment.
The 40kt DUNE Far Detector, located at the Sanford Underground
Research Facility, will offer unique capabilities for the study of
atmospheric neutrinos. Due to the detector¹s excellent energy resolutions,
angular resolutions, and particle ID capabilities, atmospheric neutrino
analyses in DUNE can provide valuable information about 3-flavor
oscillations, despite the relatively modest statistics. These data
provide a complementary analysis approach to beam neutrinos, and can help
resolve ambiguities in beam-only analyses. In this talk we will focus on
the determination of the mass hierarchy, octant of theta23, and
measurement of Delta_CP using atmospheric neutrinos in DUNE.
PROSPECT is a phased experiment consisting of segmented $^6$Li-loaded liquid scintillator antineutrino detectors designed to probe short-baseline neutrino oscillations and precisely measure the reactor antineutrino spectrum.
The experiment will be located at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory.
The first phase is a movable 3 tonne antineutrino detector located 7-12 m from the compact, highly enriched uranium core.
Over the past three years, PROSPECT has deployed multiple prototype detectors at HFIR to understand the local background environment and demonstrate active and passive background rejection.
The single-segment test detector, PROSPECT-20, verified background simulations and demonstrated the optical performance expected in the full detector.
A two-segment prototype, PROSPECT-50, is under development to demonstrate critical subsystems such as calibration, optical segmentation, light readout.
We present results of the prototype program along with projections for the performance of the PROSPECT detector.
Numerous surveys of modern particle physics indicate that the discipline is still largely a male pursuit, and one in which women and other marginalised groups continue to face discriminatory practices. The fraction of female particle physicists reduces with each career stage. Early career particle physicists face precarious employment conditions with serial short term contracts, long working hours, the frequent need to relocate, and little prospect for a permanent academic position. There are indications that these employment conditions add to the gender-imbalance in the field, but clearly, this problem directly affects both male and female early career scientists. The LHCb experiment has, as the first (and so far only) LHC experiment, created a dedicated office for Early Career Gender and Diversity (ECGD) (see http://lhcb.web.cern.ch/lhcb/ECGD_Office/ECGD-intro.html ). The ECGD office’s role is to to advise the management on ECGD matters; provide a point of contact for anybody experiencing any kind discrimination, bullying or harassment; collate regular statistics and other relevant information related to gender and, where appropriate, other ECGD matters; organise regular open meetings where ECGD matters are discussed. We report on our first year of experiences as the first ECGD officers in the LHC’s first ECGD office. Amongst the pitfalls of such an office is the potential of being perceived as either inconsequential, or as an external body that is a source of new rules and complications. We will highlight the strategies we adopted in an attempt to circumnavigate these pitfalls, aiming to be (and be seen as) an integral part of LHCb, working with the entire collaboration to achieve an environment in which all members can thrive. We will also discuss a few highlights of our programme in that year, including well-attended plenary meetings at LHCb weeks on topics such as “mentoring”, “(m/p)aternity leave”, “sexual harrassment”, “careers inside and outside HEP” - and the implementation of a mentoring scheme.
Signal events where multiple missing neutral particles are present in
a final state represent challenging topologies to search for new
physics at the LHC. The key to any search is the ability to separate
background-like events from signal-like events. Identifying such
signal-like events, and extracting their properties, is exacerbated by
a lack of knowledge of the particle masses and some missing kinematic
handles. The "Recursive Jigsaw" reconstruction technique introduces a new
approach to extracting information in events with open final states resulting from
pair-production of objects.
We demonstrate sensitive analysis strategies to search for beyond standard model signatures by de-composing the final state objects into hemispheres and further sub-dividing them where necessary, based on the topology of interest. Backgrounds are controlled without recourse to conventional approaches based on variables such as missing transverse momentum and effective mass to select regions of sensitivity. Applications of the technique will be shown.
State-of-the-art theoretical predictions accurate to next-to-leading order QCD interfaced with Pythia8 and Herwig++ event generators are tested by comparing the unfolded ttbar differential data collected with the CMS detector at 8 TeV. These predictions are also compared with the underlying event activity distributions in ttbar events using CMS proton-proton data collected in 2015 at a center of mass energy of 13 TeV.
A new tracking system is under development for operation in the CMS
experiment at the High Luminosity LHC. It includes an outer tracker which
will construct stubs, built by correlating clusters in two closely spaced
sensor layers for the rejection of hits from low transverse momentum tracks,
and transmit them off-detector at 40 MHz. If tracker data is to contribute
to keeping the Level-1 trigger rate at around 750 kHz under increased
luminosity, a crucial component of the upgrade will be the ability to
identify tracks with transverse momentum above 3 GeV/c by building tracks
out of stubs. A concept for an FPGA-based track finder using a fully
time-multiplexed architecture is presented, where track candidates are
identified using a projective binning algorithm based on the Hough
Transform. A hardware system based on the MP7 MicroTCA processing card
has been assembled, demonstrating a realistic slice of the track finder
in order to help gauge the performance and requirements for a full system.
This poster outlines the system architecture and algorithms employed,
highlighting some of the first results from the hardware demonstrator
and discusses the prospects and performance of the completed track finder.
Social media channels are vital for outreach and offer huge opportunities for scientists to directly engage with the public using nontraditional methods – including lots of creativity and humor. The physics community’s presence is growing more significant, and this session (designed for early career researchers ) will provide a lively discussion with experts in the domain. We’ll cover how to best use social media to raise public awareness of science, share excitement and progress, and cultivate support from followers. We’ll also discuss some of the thornier issues in social media, such as capturing the complexity of both the scientific process and the science itself.
Presenters:
Biron, Lauren (Fermilab)
Cowern, Dianna (Physics Girl)
Haffner, Julie (CERN)
Nellis, Clara (IN2P3)