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Study of final-state radiation in decays of Z bosons produced in pp collisions at 7 TeV
(2015)Physical Review DThe differential cross sections for the production of photons in Z→μ+μ−γ decays are presented as a function of the transverse energy of the photon and its separation from the nearest muon. The data for these measurements are collected with the CMS detector and correspond to an integrated luminosity of 4.7 fb−1 of pp collisions at √s=7 TeV delivered by the CERN LHC. The cross sections are compared to simulations with powheg and pythia, ...Journal Article -
Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at √s= 8TeV
(2014)Physical Review DThe first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7 fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the ...Journal Article -
Decomposing transverse momentum balance contributions for quenched jets in PbPb collisions at √sNN=2.76 TeV
(2016)Journal of High Energy PhysicsInteractions between jets and the quark-gluon plasma produced in heavy ion collisions are studied via the angular distributions of summed charged-particle transverse momenta (p T) with respect to both the leading and subleading jet axes in high-p T dijet events. The contributions of charged particles in different momentum ranges to the overall event p T balance are decomposed into short-range jet peaks and a long-range azimuthal asymmetry ...Journal Article -
Search in leptonic channels for heavy resonances decaying to long-lived neutral particles
(2013)Journal of High Energy PhysicsA search is performed for heavy resonances decaying to two long-lived massive neutral particles, each decaying to leptons. The experimental signature is a distinctive topology consisting of a pair of oppositely charged leptons originating at a separated secondary vertex. Events were collected by the CMS detector at the LHC during pp collisions at s√=7 TeV, and selected from data samples corresponding to 4.1 (5.1) fb−1 of integrated ...Journal Article -
Measurement of jet fragmentation in PbPb and pp collisions at √sNN = 2.76 TeV
(2014)Physical Review CThe jet fragmentation function of inclusive jets with transverse momentum pT above 100GeV/c in PbPb collisions has been measured using reconstructed charged particles with pT above 1GeV/c in a cone of radius 0.3 around the jet axis. A data sample of PbPb collisions collected in 2011 at a nucleon-nucleon center-of-mass energy of √sNN=2.76TeV corresponding to an integrated luminosity of 150μb−1 is used. The results for PbPb collisions as a ...Journal Article -
Searches for new physics using the tt ¯ invariant mass distribution in pp collisions at s √ =8 TeV
(2013)Physical Review LettersSearches for anomalous top quark-antiquark production are presented, based on pp collisions at √s=8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb−1, were collected with the CMS detector at the LHC. The observed t¯t invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space ...Journal Article -
Measurement of the differential cross sections for top quark pair production as a function of kinematic event variables in pp collisions at √s=7 and 8 TeV
(2016)Physical Review DMeasurements are reported of the normalized differential cross sections for top quark pair production with respect to four kinematic event variables: the missing transverse energy; the scalar sum of the jet transverse momentum (pT); the scalar sum of the pT of all objects in the event; and the pT of leptonically decaying W bosons from top quark decays. The data sample, collected using the CMS detector at the LHC, consists of 5.0 fb−1 of ...Journal Article -
Search for Top Squarks in R-Parity-Violating Supersymmetry Using Three or More Leptons and b-Tagged Jets
(2013)Physical Review LettersA search for anomalous production of events with three or more isolated leptons and bottom-quark jets produced in pp collisions at √s=8 TeV is presented. The analysis is based on a data sample corresponding to an integrated luminosity of 19.5 fb−1 collected by the CMS experiment at the LHC in 2012. No excess above the standard model expectations is observed. The results are interpreted in the context of supersymmetric models with ...Journal Article -
Description and performance of track and primary-vertex reconstruction with the CMS tracker akahashi
(2014)Journal of InstrumentationA description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tbar t events ...Journal Article -
Measurement of four-jet production in proton-proton collisions at √s =7TeV
(2014)Physical Review DMeasurements of the differential cross sections for the production of exactly four jets in proton-proton collisions are presented as a function of the transverse momentum pT and pseudorapidity η, together with the correlations in azimuthal angle and the pT balance among the jets. The data sample was collected in 2010 at a center-of-mass energy of 7 TeV with the CMS detector at the LHC, with an integrated luminosity of 36 pb−1. The cross ...Journal Article