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Measurement Of B Hadron Lifetimes In Pp Collisions At √S = 8 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco Yumiceva, The Cms Collaboration Jun 2018

Measurement Of B Hadron Lifetimes In Pp Collisions At √S = 8 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Measurements are presented of the lifetimes of the B ⁰, Bs0, Λb0, and Bc+ hadrons using the decay channels B0→J/ψK∗(892)0, B0→J/ψKS0, Bs0→J/ψπ+π-, Bs0→J/ψϕ(1020), Λb0→J/ψΛ0, and Bc+→J/ψπ+. The data sample, corresponding to an integrated luminosity of 19.7fb-1, was collected by the CMS detector at the LHC in proton–proton collisions at s=8TeV. The B 0 lifetime is measured to be 453.0±1.6(stat)±1.8(syst)μm in J / ψK ∗(892) 0and 457.8±2.7(stat)±2.8(syst)μm in J/ψKS0, which results in a combined measurement of cτB0=454.1±1.4(stat)±1.7(syst)μm. The effective lifetime of the Bs0 meson is measured in two decay modes, with contributions from different amounts of the heavy and light eigenstates. …


Synthesizing Broadband Propagation-Invariant Space-Time Wave Packets Using Transmissive Phase Plates, H. Esat Kondakci, Murat Yessenov, Monjurul Feeroz Meem, Danielle Reyes, Daniel J. Thui, Shermineh Rostami Fairchild, Martin C. Richardson, Rajesh Menon, Ayman F. Abouraddy May 2018

Synthesizing Broadband Propagation-Invariant Space-Time Wave Packets Using Transmissive Phase Plates, H. Esat Kondakci, Murat Yessenov, Monjurul Feeroz Meem, Danielle Reyes, Daniel J. Thui, Shermineh Rostami Fairchild, Martin C. Richardson, Rajesh Menon, Ayman F. Abouraddy

Aerospace, Physics, and Space Science Faculty Publications

Space-time wave packets are a class of pulsed optical beams that are di raction-free and dispersion-free in free space by virtue of introducing a tight correlation between the spatial and temporal degrees of freedom of the field. Such wave packets have been recently synthesized in a novel configuration that makes use of a spatial light modulator to realize the required spatio-temporal correlations. This arrangement combines pulse-modulation and beam-shaping to assign one spatial frequency to each wavelength according to a prescribed correlation function. Relying on a spatial light modulator results in several limitations by virtue of their pixelation, small area, and …


Search For A Heavy Right-Handed W Boson And A Heavy Neutrino In Events With Two Same-Flavor Leptons And Two Jets At S√=13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva May 2018

Search For A Heavy Right-Handed W Boson And A Heavy Neutrino In Events With Two Same-Flavor Leptons And Two Jets At S√=13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search for a heavy right-handed W boson (WR) decaying to a heavy right-handed neutrino and a charged lepton in events with two same-flavor leptons (e or μ) and two jets, is presented. The analysis is based on proton-proton collision data, collected by the CMS Collaboration at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb−1. No significant excess above the standard model expectation is seen in the invariant mass distribution of the dilepton plus dijet system. Assuming that couplings are identical to those of the standard model, and that only one heavy neutrino flavor NR …


Measurement Of Associated Z + Charm Production In Proton–Proton Collisions At √S=8tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva, The Cms Collaboration Apr 2018

Measurement Of Associated Z + Charm Production In Proton–Proton Collisions At √S=8tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A study of the associated production of a Z boson and a charm quark jet (Z + c), and a comparison to production with a b quark jet (Z + b), in p p collisions at a centre-of-mass energy of 8TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7fb-1, collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays …


Search For New Physics In Events With A Leptonically Decaying Z Boson And A Large Transverse Momentum Imbalance In Proton–Proton Collisions At √S = 13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration Jan 2018

Search For New Physics In Events With A Leptonically Decaying Z Boson And A Large Transverse Momentum Imbalance In Proton–Proton Collisions At √S = 13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for new physics in events with a Z boson produced in association with large missing transverse momentum at the LHC is presented. The search is based on the 2016 data sample of proton-proton collisions recorded with the CMS experiment at s=13TeV, corresponding to an integrated luminosity of 35.9fb-1. The results of this search are interpreted in terms of a simplified model of dark matter production via spin-0 or spin-1 mediators, a scenario with a standard-model-like Higgs boson produced in association with the Z boson and decaying invisibly, a model of unparticle production, and a model with large extra …


A Novel Application Of Fiber Bragg Grating (Fbg) Sensors In Mpgd, Duccio Abbaneo, Vallary Bhopatkar, Marcus Hohlmann, Ajit K. Mohapatra, Aiwu Zhang Jan 2018

A Novel Application Of Fiber Bragg Grating (Fbg) Sensors In Mpgd, Duccio Abbaneo, Vallary Bhopatkar, Marcus Hohlmann, Ajit K. Mohapatra, Aiwu Zhang

Aerospace, Physics, and Space Science Faculty Publications

We present a novel application of Fiber Bragg Grating (FBG) sensors in the construction and characterisation of Micro Pattern Gaseous Detector (MPGD), with particular attention to the realisation of the largest triple (Gas electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 m² active area each, employing three GEM foils per chamber, to be installed in the forward region of the CMS endcap during the long shutdown of LHC in 2108-2019. The large active area of each GE1/1 chamber consists of …


Azimuthal Anisotropy Of Charged Particles With Transverse Momentum Up To 100 Gev/C In Pbpb Collisions At Snn=5.02 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, M Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jan 2018

Azimuthal Anisotropy Of Charged Particles With Transverse Momentum Up To 100 Gev/C In Pbpb Collisions At Snn=5.02 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, M Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The Fourier coefficients v2 and v3 characterizing the anisotropy of the azimuthal distribution of charged particles produced in PbPb collisions at sNN=5.02 TeV are measured with data collected by the CMS experiment. The measurements cover a broad transverse momentum range, 110 GeV/c range, where anisotropic azimuthal distributions should reflect the path-length dependence of parton energy loss in the created medium. Results are presented in several bins of PbPb collision centrality, spanning the 60% most central events. The v2 coefficient is measured with the scalar product and the multiparticle cumulant methods, which have different sensitivities to initial-state fluctuations. The values from …


Measurement Of Prompt And Nonprompt Charmonium Suppression In Pbpb Collisions At 5.02 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration Jan 2018

Measurement Of Prompt And Nonprompt Charmonium Suppression In Pbpb Collisions At 5.02 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The nuclear modification factors of J / ψ and ψ(2S) mesons are measured in PbPb collisions at a centre-of-mass energy per nucleon pair of sNN=5.02TeV. The analysis is based on PbPb and p p data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464μb-1 and 28pb-1, respectively. The measurements are performed in the dimuon rapidity range of | y| < 2.4 as a function of centrality, rapidity, and transverse momentum (pT) from pT= 3 GeV/c in the most forward region and up to 50GeV/c. Both prompt and nonprompt (coming from b hadron decays) J / ψ mesons are observed to be increasingly suppressed with centrality, with a magnitude similar to the one observed at sNN=2.76TeV for the two J / ψ meson components. No dependence on rapidity is observed for either prompt or nonprompt J / ψ mesons. An indication of a lower prompt J / ψ meson suppression at pT> 25 GeV/c is seen with respect to that observed at intermediate pT. The prompt ψ(2S) meson yield is found to be more suppressed than that of the prompt J / ψ mesons in the entire …


Search For Standard Model Production Of Four Top Quarks With Same-Sign And Multilepton Final States In Proton–Proton Collisions At √S=13tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration Jan 2018

Search For Standard Model Production Of Four Top Quarks With Same-Sign And Multilepton Final States In Proton–Proton Collisions At √S=13tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for standard model production of four top quarks (t t ¯ t t ¯) is reported using events containing at least three leptons (e , μ) or a same-sign lepton pair. The events are produced in proton–proton collisions at a center-of-mass energy of 13TeV at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9fb-1. Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control regions are used to constrain the dominant backgrounds. The observed and expected signal significances are, respectively, 1.6 and 1.0 standard deviations, and the t …


Erratum 2: Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton-Proton Collisions At S√=13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, T. Roy, Francisco Yumiceva Jan 2018

Erratum 2: Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton-Proton Collisions At S√=13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, T. Roy, Francisco Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

In the original paper, figure 10 was incorrect. The correct figgure is shown below. Additionally, the unparticle entries in table 3, as well as figure 4 and 5 were labelled with incorrect values of AU. The entries correctly correspond to AU = 1TeV.


Principal-Component Analysis Of Two-Particle Azimuthal Correlations In Pbpb And Ppb Collisions At Cms, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva Dec 2017

Principal-Component Analysis Of Two-Particle Azimuthal Correlations In Pbpb And Ppb Collisions At Cms, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

For the first time a principle-component analysis is used to separate out different orthogonal modes of the two-particle correlation matrix from heavy ion collisions. The analysis uses data from sNN=2.76TeV PbPb and sNN=5.02TeV pPb collisions collected by the CMS experiment at the CERN Large Hadron Collider. Two-particle azimuthal correlations have been extensively used to study hydrodynamic flow in heavy ion collisions. Recently it was shown that the expected factorization of two-particle results into a product of the constituent single-particle anisotropies is broken. The new information provided by these modes may shed light on the breakdown of flow factorization in heavy …


Search For Pair Production Of Vector-Like T And B Quarks In Single-Lepton Final States Using Boosted Jet Substructure In Proton-Proton Collisions At √S=13 Tev, Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco X. Yumiceva Nov 2017

Search For Pair Production Of Vector-Like T And B Quarks In Single-Lepton Final States Using Boosted Jet Substructure In Proton-Proton Collisions At √S=13 Tev, Cms Collaboration, A. M. Sirunyan, A. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search for pair production of massive vector-like T and B quarks in proton-proton collisions at s=13" role="presentation" style="box-sizing: inherit; display: inline-block; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�=13 TeV is presented. The data set was collected in 2015 by the CMS experiment at the LHC and corresponds to an integrated luminosity of up to 2.6 fb−1. The T and B quarks are assumed to decay through three possible channels into a heavy boson (either a …


Measurements Of Differential Cross Sections For Associated Production Of A W Boson And Jets In Proton-Proton Collisions At Square Root Of S = 8 Tev, A. M. Sirunyan, A. R. Tumasyan, W. Adam, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva Oct 2017

Measurements Of Differential Cross Sections For Associated Production Of A W Boson And Jets In Proton-Proton Collisions At Square Root Of S = 8 Tev, A. M. Sirunyan, A. R. Tumasyan, W. Adam, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A measurement of the differential cross sections for a W boson produced in association with jets in the muon decay channel is presented. The measurement is based on 13 TeV proton-proton collision data corresponding to an integrated luminosity of 2.2 fb-1, recorded by the CMS detector at the LHC. The cross sections are reported as functions of jet multiplicity, jet transverse momentum pT, jet rapidity, the scalar pT sum of the jets, and angular correlations between the muon and each jet for different jet multiplicities. The measured cross sections are in agreement with predictions that include multileg leading-order (LO) and …


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 Oct 2017

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 Direct Production Of Supersymmetric Partners Of The Top Quark In The All-Jets Final State In Proton-Proton Collisions At √S=13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration Oct 2017

Search For Direct Production Of Supersymmetric Partners Of The Top Quark In The All-Jets Final State In Proton-Proton Collisions At √S=13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin S. Roy, F. Yumiceva, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for direct production of top squark pairs in events with jets and large transverse momentum imbalance is presented. The data are based on proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector in 2016 at the CERN LHC, and correspond to an integrated luminosity of 35.9 fb−1. The search considers a variety of R-parity conserving supersymmetric models, including ones for which the top squark and neutralino masses are nearly degenerate. Specialized jet reconstruction tools are developed to exploit the unique characteristics of the signal topologies. With no significant excess of events observed above …


Search For Low Mass Vector Resonances Decaying To Quark-Antiquark Pairs In Proton-Proton Collisions At √ S = 13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva Sep 2017

Search For Low Mass Vector Resonances Decaying To Quark-Antiquark Pairs In Proton-Proton Collisions At √ S = 13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at ffiffiffi s p ¼ 13 TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7 fb−1. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant mass of the jet. The results are interpreted in the framework of a leptophobic vector resonance and no evidence is found for such particles in the …


Measurement Of The T T ¯ Production Cross Section Using Events With One Lepton And At Least One Jet In Pp Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Sep 2017

Measurement Of The T T ¯ Production Cross Section Using Events With One Lepton And At Least One Jet In Pp Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A measurement of the t t ¯ production cross section at s=13 TeV is presented using proton-proton collisions, corresponding to an integrated luminosity of 2.2 fb−1, collected with the CMS detector at the LHC. Final states with one isolated charged lepton (electron or muon) and at least one jet are selected and categorized according to the accompanying jet multiplicity. From a likelihood fit to the invariant mass distribution of the isolated lepton and a jet identified as coming from the hadronization of a bottom quark, the cross section is measured to be σtt¯=888±2,(stat)−28+26(syst)±20(lumi) pb, in agreement with the standard model …


Measurements Of E+E− Pairs From Open Heavy Flavor In P + P And D + A Collisions At √ Snn = 200 Gev, Gyöngyi Baksay, László A. Baksay, C. Baumann, Klaus Dehmelt, Marcus Hohlmann, Jun Kikuchi, Christian Klein-Boesing, S. Rembeczki, Klaus Johannes Reygers, Baldo Sahlmueller, Johannes P. Wessels, Yoshio Yamaguchi, A. Adare Aug 2017

Measurements Of E+E− Pairs From Open Heavy Flavor In P + P And D + A Collisions At √ Snn = 200 Gev, Gyöngyi Baksay, László A. Baksay, C. Baumann, Klaus Dehmelt, Marcus Hohlmann, Jun Kikuchi, Christian Klein-Boesing, S. Rembeczki, Klaus Johannes Reygers, Baldo Sahlmueller, Johannes P. Wessels, Yoshio Yamaguchi, A. Adare

Aerospace, Physics, and Space Science Faculty Publications

We report a measurement of e+e- pairs from semileptonic heavy-flavor decays in p+p collisions at sNN=200 GeV. The e+e- pair yield from bb and cc is separated by exploiting a double differential fit done simultaneously in dielectron invariant mass and pT. We used three different event generators, pythia, mc@nlo, and powheg, to simulate the e+e- spectra from cc and bb production. The data can be well described by all three generators within the detector acceptance. However, when using the generators to extrapolate to 4π, significant differences are observed for the total cross section. These difference are less pronounced for bb …


Search For Top Quark Partners With Charge 5/3 In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Aug 2017

Search For Top Quark Partners With Charge 5/3 In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for the production of heavy partners of the top quark with charge 5/3 (X5/3) decaying into a top quark and a W boson is performed with a data sample corresponding to an integrated luminosity of 2.3 fb−1, collected in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector at the CERN LHC. Final states with either a pair of same-sign leptons or a single lepton, along with jets, are considered. No significant excess is observed in the data above the expected standard model background contribution and an X5/3 quark with right-handed (left-handed) couplings is …


Measurement Of The Inclusive Energy Spectrum In The Very Forward Direction In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Aug 2017

Measurement Of The Inclusive Energy Spectrum In The Very Forward Direction In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The differential cross section for inclusive particle production as a function of energy in proton-proton collisions at a center-of-mass energy of 13 TeV is measured in the very forward region of the CMS detector. The measurement is based on data collected with the CMS apparatus at the LHC, and corresponds to an integrated luminosity of 0.34 μb−1. The energy is measured in the CASTOR calorimeter, which covers the pseudorapidity region −6.6 < η < −5.2. The results are given as a function of the total energy deposited in CASTOR, as well as of its electromagnetic and hadronic components. The spectra are sensitive to the modeling of multiparton interactions in pp collisions, and provide new constraints for hadronic interaction models used in collider and in high energy cosmic ray physics.


Searches For W′ Bosons Decaying To A Top Quark And A Bottom Quark In Proton-Proton Collisions At 13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Aug 2017

Searches For W′ Bosons Decaying To A Top Quark And A Bottom Quark In Proton-Proton Collisions At 13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Searches are presented for heavy gauge bosons decaying into a top and a bottom quark in data collected by the CMS experiment at s=13 TeV that correspond to an integrated luminosity of 2.2 and 2.6 fb−1 in the leptonic and hadronic analyses, respectively. Two final states are analyzed, one containing a single electron, or muon, and missing transverse momentum, and the other containing multiple jets and no electrons or muons. No evidence is found for a right-handed W′ boson (W′R) and the combined analyses exclude at 95% confidence level W′R with masses below 2.4 TeV if MW′R≫MνR (mass of the …


Pseudorapidity Dependence Of Long-Range Two-Particle Correlations In Ppb Collisions At √ Snn = 5.02 Tev, V. Khachatryan, A. M. Sirunyan, Daniel Noonan, Marc M. Baarmand, Vallary Bhopatkar, Marcus Hohlmann, Stefano Colafranceschi, Tuhin S. Roy, Francisco X. Yumiceva, H Kalakhety Jul 2017

Pseudorapidity Dependence Of Long-Range Two-Particle Correlations In Ppb Collisions At √ Snn = 5.02 Tev, V. Khachatryan, A. M. Sirunyan, Daniel Noonan, Marc M. Baarmand, Vallary Bhopatkar, Marcus Hohlmann, Stefano Colafranceschi, Tuhin S. Roy, Francisco X. Yumiceva, H Kalakhety

Aerospace, Physics, and Space Science Faculty Publications

Two-particle correlations in pPb collisions at a nucleon-nucleon center-of-mass energy of 5.02TeV are studied as a function of the pseudorapidity separation (Δη) of the particle pair at small relative azimuthal angle (|Δφ|<π/3). The correlations are decomposed into a jet component that dominates the short-range correlations (|Δη|<1), and a component that persists at large Δη and may originate from collective behavior of the produced system. The events are classified in terms of the multiplicity of the produced particles. Finite azimuthal anisotropies are observed in high-multiplicity events. The second and third Fourier components of the particle-pair azimuthal correlations, V2 and V3, are extracted after subtraction of the jet component. The single-particle anisotropy parameters v2 and v3 are normalized by their laboratory frame midrapidity value and are studied as a function of ηc.m.. The normalized v2 distribution is found to be asymmetric about ηc.m.=0, with smaller values observed at forward pseudorapidity, corresponding to the direction of the proton beam, while no significant pseudorapidity dependence is observed for the normalized v3 distribution within the statistical uncertainties.


Search For Third-Generation Scalar Leptoquarks And Heavy Right-Handed Neutrinos In Final States With Two Tau Leptons And Two Jets In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For Third-Generation Scalar Leptoquarks And Heavy Right-Handed Neutrinos In Final States With Two Tau Leptons And Two Jets In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search is performed for third-generation scalar leptoquarks and heavy right-handed neutrinos in events containing one electron or muon, one hadronically decaying τ lepton, and at least two jets, using a s=13 TeV pp collision data sample corresponding to an integrated luminosity of 12.9 fb-1 collected with the CMS detector at the LHC in 2016. The number of observed events is found to be in agreement with the standard model prediction. A limit is set at 95% confidence level on the product of the leptoquark pair production cross section and β2, where β is the branching fraction of leptoquark decay …


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 Jul 2017

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 …


Search For Physics Beyond The Standard Model In Events With Two Leptons Of Same Sign, Missing Transverse Momentum, And Jets In Proton–Proton Collisions At √S=13tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For Physics Beyond The Standard Model In Events With Two Leptons Of Same Sign, Missing Transverse Momentum, And Jets In Proton–Proton Collisions At √S=13tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A data sample of events from proton–proton collisions with two isolated same-sign leptons, missing transverse momentum, and jets is studied in a search for signatures of new physics phenomena by the CMS Collaboration at the LHC. The data correspond to an integrated luminosity of 35.9fb-1, and a center-of-mass energy of 13TeV. The properties of the events are consistent with expectations from standard model processes, and no excess yield is observed. Exclusion limits at 95% confidence level are set on cross sections for the pair production of gluinos, squarks, and same-sign top quarks, as well as top-quark associated production of a …


Measurement Of Inclusive Jet Cross Sections In Pp And Pbpb Collisions At √ Snn = 2.76 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Daniel Noonan, Stefano Colafranceschi, Marcus Hohlmann, Tuhin S. Roy, Francisco X. Yumiceva Jul 2017

Measurement Of Inclusive Jet Cross Sections In Pp And Pbpb Collisions At √ Snn = 2.76 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Daniel Noonan, Stefano Colafranceschi, Marcus Hohlmann, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

Inclusive jet spectra from pp and PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76TeV, collected with the CMS detector at the CERN Large Hadron Collider, are presented. Jets are reconstructed with three different distance parameters (R=0.2, 0.3, and 0.4) for transverse momentum (pT) greater than 70GeV/c and pseudorapidity |η|<2. Next-to-leading-order quantum chromodynamic calculations with nonperturbative corrections are found to overpredict jet production cross sections in pp for small distance parameters. The jet nuclear modification factors for PbPb compared to pp collisions, show a steady decrease from peripheral to central events, along with a weak dependence on the jet pT. They are found to be independent of the distance parameter in the measured kinematic range. ©2017 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation.


Measurement Of The Jet Mass In Highly Boosted T T ¯ Events From Pp Collisions At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Measurement Of The Jet Mass In Highly Boosted T T ¯ Events From Pp Collisions At √S=8tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The first measurement of the jet mass mjet of top quark jets produced in t t ¯ events from pp collisions at s=8TeV is reported for the jet with the largest transverse momentum pT in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7fb-1. The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay t → b W with W → ℓν where ℓ is an electron or muon, are used to select t t ¯ events with large Lorentz boosts. The …


Measurement Of Double-Differential Cross Sections For Top Quark Pair Production In Pp Collisions At √S=8tev And Impact On Parton Distribution Functions, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Measurement Of Double-Differential Cross Sections For Top Quark Pair Production In Pp Collisions At √S=8tev And Impact On Parton Distribution Functions, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Normalized double-differential cross sections for top quark pair (t t ¯) production are measured in pp collisions at a centre-of-mass energy of 8TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7fb-1. The measurement is performed in the dilepton e ±μ∓ final state. The t t ¯ cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and t t ¯ system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to …


Search For New Physics With Dijet Angular Distributions In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For New Physics With Dijet Angular Distributions In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search is presented for extra spatial dimensions, quantum black holes, and quark contact interactions in measurements of dijet angular distributions in proton-proton collisions at s=13 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 2.6 fb−1. The distributions are found to be in agreement with predictions from perturbative quantum chromodynamics that include electroweak corrections. Limits for different contact interaction models are obtained. In a benchmark model, valid to next-to-leading order in QCD and in which only left-handed quarks participate, quark contact interactions are excluded up to a scale of …


Search For Dark Matter Produced With An Energetic Jet Or A Hadronically Decaying W Or Z Boson At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Jul 2017

Search For Dark Matter Produced With An Energetic Jet Or A Hadronically Decaying W Or Z Boson At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for dark matter particles is performed using events with large missing transverse momentum, at least one energetic jet, and no leptons, in proton-proton collisions at s=13 TeV collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 12.9 fb−1. The search includes events with jets from the hadronic decays of a W or Z boson. The data are found to be in agreement with the predicted background contributions from standard model processes. The results are presented in terms of simplified models in which dark matter particles are produced through interactions involving …