Physical Sciences and Mathematics | Open Access Articles

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.

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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.

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Search For Supersymmetry In Events With One Lepton And Multiple Jets In Proton-Proton Collisions At Square Root Of S = 13 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, Vallary Bhopatkar, Marcus Hohlmann, Daniel Noonan, Stefano Colafranceschi, Tuhin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search for supersymmetry is performed in events with a single electron or muon in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 2.3 fb-1. Several exclusive search regions are defined based on the number of jets and b-tagged jets, the scalar sum of the jet transverse momenta, and the scalar sum of the missing transverse momentum and the transverse momentum of the lepton. The observed event yields in data are consistent with the expected backgrounds from standard model processes. The …

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Search For R-Parity Violating Supersymmetry With Displaced Vertices In Proton-Proton Collisions At Square Root Of S = 8 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

Results are reported from a search for R-parity violating supersymmetry in proton-proton collision events collected by the CMS experiment at a center-of-mass energy of s=8 TeV. The data sample corresponds to an integrated luminosity of 17.6 fb-1. This search assumes a minimal flavor violating model in which the lightest supersymmetric particle is a long-lived neutralino or gluino, leading to a signal with jets emanating from displaced vertices. In a sample of events with two displaced vertices, no excess yield above the expectation from standard model processes is observed, and limits are placed on the pair production cross section as a …

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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

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

Aerospace, Physics, and Space Science Faculty Publications

Aerospace, Physics, and Space Science Faculty Publications