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Search for supersymmetry with photons in pp collisions at √s = 8 TeV
(2015)Physical Review DTwo searches for physics beyond the standard model in events containing photons are presented. The data sample used corresponds to an integrated luminosity of 19.7 fb−1 of proton-proton collisions at √s=8 TeV, collected with the CMS experiment at the CERN LHC. The analyses pursue different inclusive search strategies. One analysis requires at least one photon, at least two jets, and a large amount of transverse momentum imbalance, while ...Journal Article -
Measurement of the muon charge asymmetry in inclusive pp→W+X production at √s = 7 Tev and an improved determination of light parton distribution functions
(2014)Physical Review DMeasurements of the muon charge asymmetry in inclusive pp→W+X production at √s=7 TeV are presented. The data sample corresponds to an integrated luminosity of 4.7 fb−1 recorded with the CMS detector at the LHC. With a sample of more than 20 million W→μν events, the statistical precision is greatly improved in comparison to previous measurements. These new results provide additional constraints on the parton distribution functions of the ...Journal Article -
Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at √s = 13 TeV
(2017)Physical Review DA 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 ...Journal Article -
Measurements of differential cross sections for associated production of a W boson and jets in proton-proton collisions at √s = 8 TeV
(2017)Physical Review DDifferential cross sections for a W boson produced in association with jets are measured in a data sample of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb−1. The W bosons are identified through their decay mode W→μν. The cross sections are reported as functions of jet multiplicity, transverse momenta, and the scalar sum of jet transverse ...Journal Article -
Mechanical stability of the CMS strip tracker measured with a laser alignment system
(2017)Journal of InstrumentationThe CMS tracker consists of 206 m2 of silicon strip sensors assembled on carbon fibre composite structures and is designed for operation in the temperature range from −25 to +25°C. The mechanical stability of tracker components during physics operation was monitored with a few μm resolution using a dedicated laser alignment system as well as particle tracks from cosmic rays and hadron-hadron collisions. During the LHC operational period ...Journal Article -
Measurement of the top quark mass using proton-proton data at √s = 7 and 8 TeV
(2016)Physical Review DA 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 19.7fb−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 ...Journal Article -
Search for dark matter and unparticles produced in association with a Z boson in proton-proton collisions at √s = 8 TeV
(2016)Physical Review DA search for evidence of particle dark matter (DM) and unparticle production at the LHC has been performed using events containing two charged leptons, consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 fb−1 of pp collisions at the LHC at a center-of-mass energy of 8 TeV. No significant excess of events ...Journal Article -
Measurement of the Electron Charge Asymmetry in Inclusive W Production in pp Collisions at √s=7 TeV
(2012)Physical Review LettersA measurement of the electron charge asymmetry in inclusive pp→W+X→eν+X production at √s=7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 840 pb−1. The electron charge asymmetry reflects the unequal production of W+ and W− bosons in pp collisions. The electron charge asymmetry is measured in bins of the absolute value of electron pseudorapidity in the range of ...Journal Article -
Measurement of the t-Channel Single Top Quark Production Cross Section in pp Collisions at √s=7 TeV
(2011)Physical Review LettersElectroweak production of the top quark is measured for the first time in pp collisions at √s=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb−1. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. ...Journal Article -
The CMS trigger system
(2017)Journal of InstrumentationThis paper describes the CMS trigger system and its performance during Run 1 of the LHC. The trigger system consists of two levels designed to select events of potential physics interest from a GHz (MHz) interaction rate of proton-proton (heavy ion) collisions. The first level of the trigger is implemented in hardware, and selects events containing detector signals consistent with an electron, photon, muon, τ lepton, jet, or missing ...Journal Article