F. Lagarde

Search for heavy Majorana neutrinos in e+/- e+/- plus jets and e+/- mu+/- plus jets events in proton-proton collisions at sqrt(s) = 8 TeV

A bstractA search is performed for heavy Majorana neutrinos (N) decaying into a W boson and a lepton using the CMS detector at the Large Hadron Collider. A signature of two jets and either two same sign electrons or a same sign electron-muon pair is searched for using 19.7 fb−1 of data collected during 2012 in proton-proton collisions at a centre-of-mass energy of 8 TeV. The data are found to be consistent with the expected standard model (SM) background and, in the context of a Type-1 seesaw mechanism, upper limits are set on the cross section times branching fraction for production of heavy Majorana neutrinos in the mass range between 40 and 500 GeV. The results are additionally interpreted as limits on the mixing between the heavy Majorana neutrinos and the SM neutrinos. In the mass range considered, the upper limits range between 0.00015–0.72 for |VeN|2 and 6.6 × 10−5−0.47 for |VeNVμN∗|2/(|VeN|2 + |VμN|2), where VℓN is the mixing element describing the mixing of the heavy neutrino with the SM neutrino of flavour ℓ. These limits are the most restrictive direct limits for heavy Majorana neutrino masses above 200 GeV. A search is performed for heavy Majorana neutrinos (N) decaying into a W boson and a lepton using the CMS detector at the Large Hadron Collider. A signature of two jets and either two same sign electrons or a same sign electron-muon pair is searched for using 19.7 inverse femtobarns of data collected during 2012 in proton-proton collisions at a centre-of-mass energy of 8 TeV. The data are found to be consistent with the expected standard model (SM) background and, in the context of a Type-1 seesaw mechanism, upper limits are set on the cross section times branching fraction for production of heavy Majorana neutrinos in the mass range between 40 and 500 GeV. The results are additionally interpreted as limits on the mixing between the heavy Majorana neutrinos and the SM neutrinos. In the mass range considered, the upper limits range between 0.00015 - 0.72 for |V[eN]|^2 and 6.6E-5 - 0.47 for |V[eN] V*[muN]|^2 / ( |V[eN]|^2 + |V[muN]|^2 ), where V[lN] is the mixing element describing the mixing of the heavy neutrino with the SM neutrino of flavour l. These limits are the most restrictive direct limits for heavy Majorana neutrino masses above 200 GeV.

Measurement of the top quark mass using proton-proton data at

A new set of measurements of the top quark mass are presented, based on the proton-proton data recorded by the CMS experiment at the LHC at √ s = 8 TeV corresponding to a luminosity of 19.7 fb−1. The top quark mass is measured using the lepton+jets, all-jets and dilepton decay channels, giving values of 172.35 ± 0.16 (stat) ± 0.48 (syst) GeV, 172.32 ± 0.25 (stat) ± 0.59 (syst) GeV, and 172.82 ± 0.19 (stat) ± 1.22 (syst) GeV, respectively. When combined with the published CMS results at √ s = 7 TeV, they provide a top quark mass measurement of 172.44± 0.13 (stat)± 0.47 (syst) GeV. The top quark mass is also studied as a function of the event kinematical properties in the lepton+jets decay channel. No indications of a kinematic bias are observed and the collision data are consistent with a range of predictions from current theoretical models of tt production. Published in Physical Review D as doi:10.1103/PhysRevD.93.072004. c

{\sqrt{(s)}}

A bstractThe inclusive cross section for top quark pair production is measured in proton-proton collisions at s=7

Measurement of the t-tbar production cross section in the e-mu channel in proton-proton collisions at sqrt(s) = 7 and 8 TeV

\sqrt{s}=7

Correlations between jets and charged particles in PbPb and pp collisions at sqrt(s[NN])= 2.76 TeV

and 8 TeV, corresponding to 5.0 and 19.7 fb−1, respectively, with the CMS experiment at the LHC. The cross sections are measured in the electron-muon channel using a binned likelihood fit to multi-differential final state distributions related to identified b quark jets and other jets in the event. The measured cross section values are 173.6 ± 2.1(stat)− 4.0+ 4.5(syst) ± 3.8(lumi)pb at s=7

Measurement of inclusive jet production and nuclear modifications in pPb collisions at sqrt(s[NN]) = 5.02 TeV

\sqrt{s}=7