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Measurement Of The B± Meson Nuclear Modification Factor In Pb-Pb Collisions At Snn =5.02 Tev, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Toohin S. Roy, Francisco X. Yumiceva
Measurement Of The B± Meson Nuclear Modification Factor In Pb-Pb Collisions At Snn =5.02 Tev, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Toohin S. Roy, Francisco X. Yumiceva
Aerospace, Physics, and Space Science Faculty Publications
The differential production cross sections of B± mesons are measured via the exclusive decay channels B±→J/ψK±→μ+μ-K± as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy sNN=5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb-Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0 pb-1 (351 μb-1). The measurement is performed in the B± meson transverse momentum range of 7 to 50 GeV/c, in the rapidity interval |y|<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma. © 2017 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the «https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Search For Supersymmetry In The All-Hadronic Final State Using Top Quark Tagging In Pp Collisions At Square Root Of S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Stefano Colafranceschi, Vallary Bhopatkar, Daniel Noonan, Marcus Hohlmann, Tuhin S. Roy, Francisco X. Yumiceva
Search For Supersymmetry In The All-Hadronic Final State Using Top Quark Tagging In Pp Collisions At Square Root Of S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Stefano Colafranceschi, Vallary Bhopatkar, Daniel Noonan, Marcus Hohlmann, Tuhin S. Roy, Francisco X. Yumiceva
Aerospace, Physics, and Space Science Faculty Publications
A search is presented for supersymmetry in all-hadronic events with missing transverse momentum and tagged top quarks. The data sample was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 2.3 fb-1 of proton-proton collisions at a center-of-mass energy of 13 TeV. Search regions are defined using the properties of reconstructed jets, the multiplicity of bottom and top quark candidates, and an imbalance in transverse momentum. With no statistically significant excess of events observed beyond the expected contributions from the standard model, we set exclusion limits at 95% confidence level on the masses of …
Measurement Of Differential Cross Sections For Top Quark Pair Production Using The Lepton + Jets Final State In Proton-Proton Collisions At 13 Tev, A. M. Sirunyan, V. Khachatryan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, Vallary Bhopatkar, Stefano Colafranceschi, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Measurement Of Differential Cross Sections For Top Quark Pair Production Using The Lepton + Jets Final State In Proton-Proton Collisions At 13 Tev, A. M. Sirunyan, V. Khachatryan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, Vallary Bhopatkar, Stefano Colafranceschi, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Aerospace, Physics, and Space Science Faculty Publications
Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at 13 TeV are measured as a function of jet multiplicity and of kinematic variables of the top quarks and the top quark-antiquark system. This analysis is based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 2.3 fb-1. The measurements are performed in the lepton+jets decay channels with a single muon or electron in the final state. The differential cross sections are presented at particle level, within a phase space close to the experimental acceptance, and at …
Search For Long-Lived Charged Particles In Proton-Proton Collisions At √S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Search For Long-Lived Charged Particles In Proton-Proton Collisions At √S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Aerospace, Physics, and Space Science Faculty Publications
Results are presented of a search for heavy stable charged particles produced in proton-proton collisions at √s = 13 TeV using a data sample corresponding to an integrated luminosity of 2.5 fb-1 collected in 2015 with the CMS detector at the CERN LHC. The search is conducted using signatures of anomalously high energy deposits in the silicon tracker and long time-of-flight measurements by the muon system. The data are consistent with the expected background, and upper limits are set on the cross sections for production of long-lived gluinos, top squarks, tau sleptons, and leptonlike long-lived fermions. These upper limits are …
Measurements Of T¯T Spin Correlations And Top Quark Polarization Using Dilepton Final States In Pp Collisions At Square Root Of S = 8 Tev, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, H Kalakhety, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Measurements Of T¯T Spin Correlations And Top Quark Polarization Using Dilepton Final States In Pp Collisions At Square Root Of S = 8 Tev, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, H Kalakhety, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva
Aerospace, Physics, and Space Science Faculty Publications
Measurements of the top quark-antiquark (tt¯) spin correlations and the top quark polarization are presented for tt¯ pairs produced in pp collisions at s=8 TeV. The data correspond to an integrated luminosity of 19.5 fb-1 collected with the CMS detector at the LHC. The measurements are performed using events with two oppositely charged leptons (electrons or muons) and two or more jets, where at least one of the jets is identified as originating from a bottom quark. The spin correlations and polarization are measured from the angular distributions of the two selected leptons, both inclusively and differentially, with respect to …
Measurement Of The B0 Production Cross Section In Pp Collisions At √S= 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov
Measurement Of The B0 Production Cross Section In Pp Collisions At √S= 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Measurements of the differential production cross sections d =dpB T and d =dyB for B0 mesons produced in pp collisions at ffiffi s p ¼ 7 TeV are presented. The data set used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 pb 1. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J=c K0 S, with the subsequent decays J=c ! þ and K0 S ! þ . The total cross section for pB T > 5 GeV and jyBj < 2:2 is measured to be 33:2 2:5 3:5 b, where the first uncertainty is statistical and the second is systematic.
Search For Neutral Minimal Supersymmetric Standard Model Higgs Bosons Decaying To Tau Pairs In Pp Collisions At √S = 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Search For Neutral Minimal Supersymmetric Standard Model Higgs Bosons Decaying To Tau Pairs In Pp Collisions At √S = 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb 1 recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the …
Search For Supersymmetry In Pp Collisions At √S = 7 Tev In Events With Two Photons And Missing Transverse Energy, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Search For Supersymmetry In Pp Collisions At √S = 7 Tev In Events With Two Photons And Missing Transverse Energy, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
A search for supersymmetry in the context of general gauge-mediated breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 pb 1 recorded by the CMS experiment at the LHC. The search is performed by using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for general gauge-mediated supersymmetry between 0.3 and 1.1 pb at the …
Measurement Of Dijet Angular Distributions And Search For Quark Compositeness In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Measurement Of Dijet Angular Distributions And Search For Quark Compositeness In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at ffiffi s p ¼ 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb 1. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of þ ¼ 5:6 TeV ( ¼ 6:7 TeV) for destructive (constructive) interference is obtained at the 95% …
Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at ffiffi s p ¼ 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb 1. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times 2 as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at …
Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at ffiffi s p ¼ 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb 1. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times 2 as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at …
Dijet Azimuthal Decorrelations In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov
Dijet Azimuthal Decorrelations In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Measurements of dijet azimuthal decorrelations in pp collisions at √s=7TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9pb-1. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation. © 2011 CERN, for the CMS Collaboration.
Measurement Of The B+ Production Cross Section In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Measurement Of The B+ Production Cross Section In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
Measurements of the total and differential cross sections d =dpB T and d =dyB for Bþ mesons produced in pp collisions at ffiffi s p ¼ 7 TeV are presented. The data correspond to an integrated luminosity of 5:8 pb 1 collected by the CMS experiment operating at the LHC. The exclusive decay Bþ ! J=c Kþ, with J=c ! þ , is used to detect Bþ mesons and to measure the production cross section as a function of pB T and yB. The total cross section for pB T > 5 GeV and jyBj < 2:4 is measured to be 28:1 2:4 2:0 3:1 b, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.
Measurement Of The Isolated Prompt Photon Production Cross Section In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Measurement Of The Isolated Prompt Photon Production Cross Section In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E T in pp collisions at ffiffi s p ¼ 7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2:9 pb 1. Photons are required to have a pseudorapidity j j < 1:45 and E T > 21 GeV, covering the kinematic region 0:006 < xT < 0:086. The measured cross section is found to be in agreement with nextto-leading-order perturbative QCD calculations.
Search For Stopped Gluinos In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Search For Stopped Gluinos In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain
Aerospace, Physics, and Space Science Faculty Publications
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1 1032 cm2 s1, an integrated luminosity of 10 pb1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino …