Study of W boson production in PbPb and pp collisions at sqrt(s[NN]) = 2.76 TeV

A measurement is presented of W-boson production in PbPb collisions carried out at a nucleon-nucleon (NN) centre-of-mass energy sqrt(s[NN]) of 2.76 TeV at the LHC using the CMS detector. In data corresponding to an integrated luminosity of 7.3 inverse microbarns, the number of W to mu mu-neutrino decays is extracted in the region of muon pseudorapidity abs(eta[mu])<2.1 and transverse momentum pt[mu]>25 GeV. Yields of muons found per unit of pseudorapidity correspond to (159 +/- 10 (stat.) +/- 12 (syst.)) 10E-8 W(plus) and (154 +/- 10 (stat.) +/- 12 (syst.)) 10E-8 W(minus) bosons per minimum-bias PbPb collision. The dependence of W production on the centrality of PbPb collisions is consistent with a scaling of the yield by the number of incoherent NN collisions. The yield of W bosons is also studied in a sample of pp interactions at sqrt(s)= 2.76 TeV corresponding to an integrated luminosity of 231 inverse nanobarns. The individual W(plus) and W(minus) yields in PbPb and pp collisions are found to agree, once the neutron and proton content in Pb nuclei is taken into account. Likewise, the difference observed in the dependence of the positive and negative muon production on pseudorapidity is consistent with next-to-leading order perturbative QCD calculations.Comment: Submitted to Physics Letters

Search for R-parity violating supersymmetry in pp collisions at root s=13 TeV using bjets in a final state with a single lepton, many jets, and high sum of large-radius jet masses

Results are reported from a search for physics beyond the standard model in proton-proton collisions at a center-of-mass energy of root s=13TeV. The search uses a signature of a single lepton, large jet and bottom quark jet multiplicities, and high sum of large-radius jet masses, without any requirement on the missing transverse momentum in an event. The data sample corresponds to an integrated luminosity of 35.9 fb(-1) recorded by the CMS experiment at the LHC. No significant excess beyond the prediction from standard model processes is observed. The results are interpreted in terms of upper limits on the production cross section for R-parity violating supersymmetric extensions of the standard model using a benchmark model of gluino pair production, in which each gluino decays promptly via (g) over tilde -> tbs. Gluinos with a mass below 1610 GeV are excluded at 95% confidence level. (c) 2018 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).Peer reviewe

Measurement of the inelastic proton-proton cross section at root s=13 TeV

A measurement of the inelastic proton-proton cross section with the CMS detector at a center-of-mass energy of root s = 13 TeV is presented. The analysis is based on events with energy deposits in the forward calorimeters, which cover pseudorapidities of -6.6 4.1 GeV and/or M-Y > 13 GeV, where M-x and M-Y are the masses of the diffractive dissociation systems at negative and positive pseudorapidities, respectively. The results are compared with those from other experiments as well as to predictions from high-energy hadron-hadron interaction models

Search for R-parity violating supersymmetry in pp collisions at root s=13 TeV using bjets in a final state with a single lepton, many jets, and high sum of large-radius jet masses

Results are reported from a search for physics beyond the standard model in proton-proton collisions at a center-of-mass energy of root s=13TeV. The search uses a signature of a single lepton, large jet and bottom quark jet multiplicities, and high sum of large-radius jet masses, without any requirement on the missing transverse momentum in an event. The data sample corresponds to an integrated luminosity of 35.9 fb(-1) recorded by the CMS experiment at the LHC. No significant excess beyond the prediction from standard model processes is observed. The results are interpreted in terms of upper limits on the production cross section for R-parity violating supersymmetric extensions of the standard model using a benchmark model of gluino pair production, in which each gluino decays promptly via (g) over tilde -> tbs. Gluinos with a mass below 1610 GeV are excluded at 95% confidence level. (c) 2018 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3)

Search for WH production with a light Higgs boson decaying to prompt electron-jets in proton-proton collisions at s\sqrt{s}=7 TeV with the ATLAS detector

A search is performed for WH production with a light Higgs boson decaying to hidden-sector particles resulting in clusters of collimated electrons, known as electron-jets. The search is performed with 2.04 fb-1 of data collected in 2011 with the ATLAS detector at the LHC in proton-proton collisions at $\sqrt{s}$=7 TeV. One event satisfying the signal selection criteria is observed, which is consistent with the expected background rate. Limits on the product of the WH production cross section and the branching ratio of a Higgs boson decaying to prompt electron-jets are calculated as a function of a Higgs boson mass in the range from 100 GeV to 140 GeV.Peer Reviewe