T. Bergauer
A5114334441- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Neutrino Physics Research
- Radiation Detection and Scintillator Technologies
- CCD and CMOS Imaging Sensors
- Astrophysics and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Radiation Therapy and Dosimetry
- Medical Imaging Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Silicon Carbide Semiconductor Technologies
- Silicon and Solar Cell Technologies
- Radiation Effects in Electronics
- Semiconductor materials and devices
- Atomic and Subatomic Physics Research
- Advancements in Semiconductor Devices and Circuit Design
- Integrated Circuits and Semiconductor Failure Analysis
- Distributed and Parallel Computing Systems
- Particle accelerators and beam dynamics
Institute of High Energy Physics
2016-2025
Austrian Academy of Sciences
2015-2024
A. Alikhanyan National Laboratory
2014-2024
University of Antwerp
2024
National and Kapodistrian University of Athens
2016
European Organization for Nuclear Research
2010-2014
High Energy Accelerator Research Organization
2012
Tohoku University
2012
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2009
Center for Migration Studies of New York
2008
Results are presented from searches for the standard model Higgs boson in proton-proton collisions at sqrt(s) = 7 and 8 TeV Compact Muon Solenoid experiment LHC, using data samples corresponding to integrated luminosities of up 5.1 inverse femtobarns 5.3 TeV. The search is performed five decay modes: gamma gamma, ZZ, WW, tau tau, b b-bar. An excess events observed above expected background, with a local significance 5.0 deviations, mass near 125 GeV, signalling production new particle. that...
The Compact Muon Solenoid (CMS) detector is described. operates at the Large Hadron Collider (LHC) CERN. It was conceived to study proton-proton (and lead-lead) collisions a centre-of-mass energy of 14 TeV (5.5 nucleon-nucleon) and luminosities up 1034 cm−2 s−1 (1027 s−1). At core CMS sits high-magnetic-field large-bore superconducting solenoid surrounding an all-silicon pixel strip tracker, lead-tungstate scintillating-crystals electromagnetic calorimeter, brass-scintillator sampling hadron...
CMS is a general purpose experiment, designed to study the physics of pp collisions at 14 TeV Large Hadron Collider (LHC). It currently involves more than 2000 physicists from 150 institutes and 37 countries. The LHC will provide extraordinary opportunities for particle based on its unprecedented collision energy luminosity when it begins operation in 2007.
The CMS apparatus was identified, a few years before the start of LHC operation at CERN, to feature properties well suited particle-flow (PF) reconstruction: highly-segmented tracker, fine-grained electromagnetic calorimeter, hermetic hadron strong magnetic field, and an excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned detector therefore developed has been consistently used in physics analyses for first time collider. For each collision, comprehensive list...
Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center-of-mass energies of 0.9, 2.36, and 7 TeV are presented, using data collected with the CMS detector over a broad range pseudorapidity (eta) azimuthal angle (phi). Short-range Delta(eta), which studied minimum bias events, characterized simple "independent cluster" parametrization order to quantify their strength (cluster size) extent eta decay width). Long-range differentially as...
This paper describes the CMS trigger system and its performance during Run 1 of LHC. The consists two levels designed to select events potential physics interest from a GHz (MHz) interaction rate proton-proton (heavy ion) collisions. first level is implemented in hardware, selects containing detector signals consistent with an electron, photon, muon, τ lepton, jet, or missing transverse energy. A programmable menu up 128 object-based algorithms used for subsequent processing. thresholds are...
Properties of the Higgs boson with mass near 125 $$\,\text {GeV}$$ are measured in proton-proton collisions CMS experiment at LHC. Comprehensive sets production and decay measurements combined. The channels include $$\gamma \gamma $$ , $$\mathrm{Z}\mathrm{Z}$$ $$\mathrm{W}\mathrm{W}$$ $$\tau \tau $$\mathrm{b} \mathrm{b} $$\mu \mu pairs. data samples were collected 2011 2012 correspond to integrated luminosities up 5.1 {fb}^\text {-1}$$ 7 {TeV}$$ 19.7 8 . From high-resolution channels, is...
Combined results are reported from searches for the standard model Higgs boson in proton-proton collisions at sqrt(s)=7 TeV five decay modes: gamma pair, b-quark tau lepton W and Z pair. The explored mass range is 110-600 GeV. analysed data correspond to an integrated luminosity of 4.6-4.8 inverse femtobarns. expected excluded absence 118-543 GeV 95% CL. observed exclude 127-600 CL, 129-525 99% An excess events above background low end making limits weaker than a signal. largest excess, with...
Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the CMS detector LHC, using data sample corresponding to an integrated luminosity 6.7 inverse microbarns. Jets are reconstructed deposited calorimeters and as function collision centrality. With increasing centrality, striking imbalance dijet transverse momentum is observed, consistent jet quenching. The observed effect extends from lower cut-off used this study (jet = 120 GeV/c) up...
Results on two-particle angular correlations for charged particles emitted in pPb collisions at a nucleon–nucleon center-of-mass energy of 5.02 TeV are presented. The analysis uses two million collected with the CMS detector LHC. studied over broad range pseudorapidity, η, and full azimuth, ϕ, as function particle multiplicity transverse momentum, pT. In high-multiplicity events, long-range (2<|Δη|<4), near-side (Δϕ≈0) structure emerges Δη–Δϕ correlation functions. This is first observation...
Measurements of the jet energy calibration and transverse momentum resolution in CMS are presented, performed with a data sample collected proton-proton collisions at centre-of-mass 7TeV, corresponding to an integrated luminosity 36pb−1. The balance dijet γ/Z+jets events is used measure response detector, as well resolution. results presented for three different methods reconstruct jets: calorimeter-based approach, ``Jet-Plus-Track'' which improves measurement calorimeter jets by exploiting...
A detailed description is reported of the analysis used by CMS Collaboration in search for standard model Higgs boson pp collisions at LHC, which led to observation a new boson. The data sample corresponds integrated luminosities up 5.1 inverse femtobarns sqrt(s) = 7 TeV, and 5.3 8 TeV. results five decay modes gamma gamma, ZZ, WW, tau tau, bb, show combined local significance 5 deviations near 125 GeV, are reviewed. fit invariant mass two high resolution channels, ZZ 4 ell, gives estimate...
New sets of parameters (“tunes”) for the underlying-event (UE) modelling pythia8, pythia6 and herwig++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton–proton ( $$\mathrm {p}\mathrm {p}$$ ) data at $$\sqrt{s} = 7\,\text {TeV} $$ proton–antiproton {p}\overline{\mathrm{p}} from CDF experiment lower $$\sqrt{s}$$ , used study models constrain their parameters, providing thereby improved predictions collisions 13 $$\,\text...
The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns data collected pp collisions at sqrt(s) = 7 TeV the LHC 2010. A few benchmark sets selection criteria covering a wide range physics analysis needs have examined. For all considered selections, efficiency to reconstruct identify with transverse momentum pT larger than GeV is above 95% over whole region pseudorapidity covered by system, abs(eta) < 2.4, while probability...
Many measurements and searches for physics beyond the standard model at LHC rely on efficient identification of heavy-flavour jets, i.e. jets originating from bottom or charm quarks. In this paper, discriminating variables algorithms used jet during first years operation CMS experiment in proton-proton collisions a centre-of-mass energy 13 TeV, are presented. Heavy-flavour have been improved compared to those previously energies 7 8 TeV. For with transverse momenta range expected simulated...
Improved jet energy scale corrections, based on a data sample corresponding to an integrated luminosity of 19.7 inverse-femtobarns collected by the CMS experiment in proton-proton collisions at center-of-mass 8 TeV, are presented. The corrections as function pseudorapidity eta and transverse momentum pT extracted from simulated events combining several channels methods. They account successively for effects pileup, uniformity detector response, residual data-simulation differences. Further...
Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at $\sqrt{s}=7\text{ }\text{ }\mathrm{TeV}$ are measured with the inner tracking system of CMS detector LHC. The charged-hadron yield is obtained by counting number reconstructed hits, hit pairs, fully charged-particle tracks. combination three methods gives a multiplicity per unit...
The properties of a Higgs boson candidate are measured in the $H\ensuremath{\rightarrow}ZZ\ensuremath{\rightarrow}4\ensuremath{\ell}$ decay channel, with $\ensuremath{\ell}=e$, $\ensuremath{\mu}$, using data from $pp$ collisions corresponding to an integrated luminosity $5.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ at center-of-mass energy $\sqrt{s}=7\text{ }\mathrm{TeV}$ and $19.7\text{ }{\mathrm{fb}}^{\ensuremath{-}\text{1}}$ $\sqrt{s}=8\text{ }\mathrm{TeV}$, recorded CMS detector...
A joint measurement is presented of the branching fractions $B^0_s\to\mu^+\mu^-$ and $B^0\to\mu^+\mu^-$ in proton-proton collisions at LHC by CMS LHCb experiments. The data samples were collected 2011 a centre-of-mass energy 7 TeV, 2012 8 TeV. combined analysis produces first observation decay, with statistical significance exceeding six standard deviations, best its fraction so far. Furthermore, evidence for decay obtained three deviations. measurements are statistically compatible SM...
The transverse momentum spectra of charged particles have been measured in pp and PbPb collisions at $\sqrt{s_{NN}}=2.76~\mathrm{TeV}$ by the CMS experiment LHC. In range p T=5–10 GeV/c, particle yield most central is suppressed up to a factor 7 compared scaled number incoherent nucleon–nucleon collisions. At higher T, this suppression significantly reduced, approaching roughly 2 for with T T=40–100 GeV/c.
Measurements of two- and four-particle angular correlations for charged particles emitted in pPb collisions are presented over a wide range pseudorapidity full azimuth. The data, corresponding to an integrated luminosity approximately 31 inverse nanobarns, were collected during the 2013 LHC run at nucleon-nucleon center-of-mass energy 5.02 TeV by CMS experiment. results compared 2.76 semi-peripheral PbPb collision 2011 run, covering similar particle multiplicities. observed characterized...
Combined measurements of the production and decay rates Higgs boson, as well its couplings to vector bosons fermions, are presented. The analysis uses LHC proton-proton collision data set recorded with CMS detector in 2016 at $\sqrt{s} =$ 13 TeV, corresponding an integrated luminosity 35.9 fb$^{-1}$. combination is based on analyses targeting five main boson mechanisms (gluon fusion, associated a W or Z top quark-antiquark pair) following modes: H $\to$ $\gamma\gamma$, ZZ, WW, $\tau\tau$,...
Observation of the diphoton decay mode recently discovered Higgs boson and measurement some its properties are reported. The analysis uses entire dataset collected by CMS experiment in proton-proton collisions during 2011 2012 LHC running periods. data samples correspond to integrated luminosities 5.1[Formula: see text]at [Formula: text] 19.7[Formula: 8[Formula: . A clear signal is observed channel at a mass close 125[Formula: with local significance text], where expected for standard model...
The CMS muon detector system, reconstruction software, and high-level trigger underwent significant changes in 2013-2014 preparation for running at higher LHC collision energy instantaneous luminosity. performance of the modified system is studied using proton-proton data center-of-mass $\sqrt{s}=$ 13 TeV, collected 2015 2016. measured parameters, including spatial resolution, efficiency, timing, are found to meet all design specifications well reproduced by simulation. Despite more...
Results are presented from a search for particle dark matter (DM), extra dimensions, and unparticles using events containing jet an imbalance in transverse momentum. The data were collected by the CMS detector proton-proton collisions at LHC correspond to integrated luminosity of 19.7 inverse femtobarns centre-of-mass energy 8 TeV. number observed is found be consistent with standard model prediction. Limits placed on DM-nucleon scattering cross section as function DM mass spin-dependent...