A search is presented for physics beyond the standard model (BSM) in final states with a pair of ... more A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy√ s= 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the ...
The azimuthal anisotropy of charged particles in Pb-Pb collisions at ffiffiffiffiffiffiffiffi sNN... more The azimuthal anisotropy of charged particles in Pb-Pb collisions at ffiffiffiffiffiffiffiffi sNN p ¼ 2: 76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pT) range up to approximately 60 GeV= c. The data cover both the low-pT region associated with hydrodynamic flow phenomena and the high-pT region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged ...
Konigsberg, J and Korytov, A and Kropivnitskaya, A and Kypreos, T and Low, JF and Matchev, K and ... more Konigsberg, J and Korytov, A and Kropivnitskaya, A and Kypreos, T and Low, JF and Matchev, K and Milenovic, P and Mitselmakher, G and Muniz, L and Remington, R and Rinkevicius, A and Sellers, P and Skhirtladze, N and Snowball, M and Yelton, J and Zakaria, M and Gaultney, V and Lebolo, LM and Linn, S and Markowitz, P and Martinez, G and Rodriguez, JL and Adams, T and Askew, A and Bochenek, J and Chen, J and Diamond, B and Gleyzer, SV and Haas, J and Hagopian, S and Hagopian, V and Jenkins, M and ...
M and Houtz, R and Ko, W and Kopecky, A and Lander, R and Mall, O and Miceli, T and Nelson, R and... more M and Houtz, R and Ko, W and Kopecky, A and Lander, R and Mall, O and Miceli, T and Nelson, R and Pellett, D and Rutherford, B and Searle, M and Smith, J and Squires, M and Tripathi, M and Vasquez Sierra, R and Andreev, V and Cline, D and Cousins, R and Duris, J and Erhan, S and Everaerts, P and Farrell, C and Hauser, J and Ignatenko, M and Plager, C and Rakness, G and Schlein, P and Tucker, J and Valuev, V and Weber, M and Babb, J and Clare, R and Dinardo, ME and Ellison, J and Gary, JW and Giordano, F and Hanson, G ...
Results are presented from a search for new physics in the final state containing a photon () and... more Results are presented from a search for new physics in the final state containing a photon () and missing transverse energy (6ET). The data correspond to an integrated luminosity of 5: 0 fb À1 collected in pp collisions at ffiffiffi sp ¼ 7 TeV by the CMS experiment. The observed event yield agrees with standardmodel expectations for the þ 6ET events. Using models for the production of dark-matter particles (), we set 90% confidence level (CL) upper limits of 13.6–15.4 fb on production in the þ 6ET state. These provide the most sensitive upper ...
A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed u... more A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed using pp collision data collected at s= 7TeV by the CMS experiment in 2011. The data sample corresponds to an integrated luminosity of approximately 5 fb− 1. The event yields observed in the signal regions are consistent with predictions of the standard model backgrounds, and upper limits on the cross section times branching fraction for a resonance decaying to dileptons are extracted from a shape analysis of the dilepton invariant mass ...
The performance of the Local Trigger based on the drift-tube system of the CMS experiment has bee... more The performance of the Local Trigger based on the drift-tube system of the CMS experiment has been studied using muons from cosmic ray events collected during the commissioning of the detector in 2008. The properties of the system are extensively tested and compared with the simulation. The effect of the random arrival time of the cosmic rays on the trigger performance is reported, and the results are compared with the design expectations for proton-proton collisions and with previous measurements obtained with ...
A search for a Higgs boson in the four-lepton decay channel H! ZZ, with each Z boson decaying to ... more A search for a Higgs boson in the four-lepton decay channel H! ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range of 110< mH< 600 GeV. The analysis uses data corresponding to an integrated luminosity of 4: 7 fbÀ1 recorded by the CMS detector in pp collisions at ffiffiffi sp ¼ 7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m4 '> 100 GeV (with 13 below 160 GeV), while 67: 1 Æ 6: 0 (9: 5 Æ 1: 3) events are expected ...
2: 76 TeV with the CMS detector at the LHC, in a 7: 2 bÀ1 data sample. The number of opposite-sig... more 2: 76 TeV with the CMS detector at the LHC, in a 7: 2 bÀ1 data sample. The number of opposite-sign muon pairs observed in the 60–120 GeV= c 2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of ½33: 8 Æ 5: 5ðstatÞ Æ 4: 4ðsystÞ Â 10 À8, in the jyj< 2: 0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.
A measurement of the double-differential inclusive dijet production cross section in proton–proto... more A measurement of the double-differential inclusive dijet production cross section in proton–proton collisions at View the MathML source is presented as a function of the dijet invariant mass and jet rapidity. The data correspond to an integrated luminosity of 36 pb− 1, recorded with the CMS detector at the LHC. The measurement covers the dijet mass range 0.2 TeV to 3.5 TeV and jet rapidities up to| y|= 2.5. It is found to be in good agreement with next-to-leading-order QCD predictions.
A search for physics beyond the standard model in events with at least three leptons and any numb... more A search for physics beyond the standard model in events with at least three leptons and any number of jets is presented. The data sample corresponds to 35 pb− 1 of integrated luminosity in pp collisions at s= 7 TeV collected by the CMS experiment at the LHC. A number of exclusive multileptonic channels are investigated and standard model backgrounds are suppressed by requiring sufficient missing transverse energy, invariant mass inconsistent with that of the Z boson, or high jet activity. Control samples in data are ...
A search for narrow resonances at high mass in the dimuon and dielectron channels has been perfor... more A search for narrow resonances at high mass in the dimuon and dielectron channels has been performed by the CMS experiment at the CERN LHC, using pp collision data recorded at TeV. The event samples correspond to integrated luminosities of 40 pb− 1 in the dimuon channel and 35 pb− 1 in the dielectron channel. Heavy dilepton resonances are predicted in theoretical models with extra gauge bosons (Z′) or as Kaluza-Klein graviton excitations (G KK) in the Randall-Sundrum model. Upper limits on the inclusive ...
A measurement of the underlying activity in events with a jet of transverse momentum in the sever... more A measurement of the underlying activity in events with a jet of transverse momentum in the several GeV region is performed in proton-proton collisions at and 7 TeV, using data collected by the CMS experiment at the LHC. The production of charged particles with pseudorapidity| η|< 2 and transverse momentum p T> 0. 5 GeV/c is studied in the azimuthal region transverse to that of the leading set of charged particles forming a track-jet. A significant growth of the average multiplicity and scalar-p T sum of the particles in the ...
Journal of physics. G, Nuclear and particle physics, 2007
DI-fusion, le Dépôt institutionnel numérique de l'ULB, est l'outil de référencementde l... more DI-fusion, le Dépôt institutionnel numérique de l'ULB, est l'outil de référencementde la production scientifique de l'ULB.L'interface de recherche DI-fusion permet de consulter les publications des chercheurs de l'ULB et les thèses qui y ont été défendues.
Combined results are reported from searches for the standard model Higgs boson in proton–proton c... more Combined results are reported from searches for the standard model Higgs boson in proton–proton collisions at s= 7 TeV in five Higgs boson decay modes: γγ, bb, ττ, WW, and ZZ. The explored Higgs boson mass range is 110–600 GeV. The analysed data correspond to an integrated luminosity of 4.6–4.8 fb− 1. The expected excluded mass range in the absence of the standard model Higgs boson is 118–543 GeV at 95% CL. The observed results exclude the standard model Higgs boson in the mass range 127–600 GeV at 95% CL, and in the ...
The top quark is pair-produced in pp collisions through quark-antiquark annihilation and gluon-gl... more The top quark is pair-produced in pp collisions through quark-antiquark annihilation and gluon-gluon fusion. The measurement of the tt cross section tests the QCD calculations for the pair production of a massive colored triplet. These calculations have been performed in perturbation theory to next-to-leading-order [1, 2]. Recent work on corrections for soft gluon emission shows that their effect on the cross section is small, and that they reduce the theoretical uncertainty arising from the choice of renormalization and factorization scales ...
Page 1. EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/2011-024 2011/03/18 CMS-EWK-... more Page 1. EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/2011-024 2011/03/18 CMS-EWK-10-006 Measurement of the Lepton Charge Asymmetry in Inclusive W Production in pp Collisions at √ s = 7 TeV The CMS Collaboration ∗ Abstract ...
A search is presented for physics beyond the standard model (BSM) in final states with a pair of ... more A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy√ s= 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the ...
The azimuthal anisotropy of charged particles in Pb-Pb collisions at ffiffiffiffiffiffiffiffi sNN... more The azimuthal anisotropy of charged particles in Pb-Pb collisions at ffiffiffiffiffiffiffiffi sNN p ¼ 2: 76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pT) range up to approximately 60 GeV= c. The data cover both the low-pT region associated with hydrodynamic flow phenomena and the high-pT region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged ...
Konigsberg, J and Korytov, A and Kropivnitskaya, A and Kypreos, T and Low, JF and Matchev, K and ... more Konigsberg, J and Korytov, A and Kropivnitskaya, A and Kypreos, T and Low, JF and Matchev, K and Milenovic, P and Mitselmakher, G and Muniz, L and Remington, R and Rinkevicius, A and Sellers, P and Skhirtladze, N and Snowball, M and Yelton, J and Zakaria, M and Gaultney, V and Lebolo, LM and Linn, S and Markowitz, P and Martinez, G and Rodriguez, JL and Adams, T and Askew, A and Bochenek, J and Chen, J and Diamond, B and Gleyzer, SV and Haas, J and Hagopian, S and Hagopian, V and Jenkins, M and ...
M and Houtz, R and Ko, W and Kopecky, A and Lander, R and Mall, O and Miceli, T and Nelson, R and... more M and Houtz, R and Ko, W and Kopecky, A and Lander, R and Mall, O and Miceli, T and Nelson, R and Pellett, D and Rutherford, B and Searle, M and Smith, J and Squires, M and Tripathi, M and Vasquez Sierra, R and Andreev, V and Cline, D and Cousins, R and Duris, J and Erhan, S and Everaerts, P and Farrell, C and Hauser, J and Ignatenko, M and Plager, C and Rakness, G and Schlein, P and Tucker, J and Valuev, V and Weber, M and Babb, J and Clare, R and Dinardo, ME and Ellison, J and Gary, JW and Giordano, F and Hanson, G ...
Results are presented from a search for new physics in the final state containing a photon () and... more Results are presented from a search for new physics in the final state containing a photon () and missing transverse energy (6ET). The data correspond to an integrated luminosity of 5: 0 fb À1 collected in pp collisions at ffiffiffi sp ¼ 7 TeV by the CMS experiment. The observed event yield agrees with standardmodel expectations for the þ 6ET events. Using models for the production of dark-matter particles (), we set 90% confidence level (CL) upper limits of 13.6–15.4 fb on production in the þ 6ET state. These provide the most sensitive upper ...
A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed u... more A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed using pp collision data collected at s= 7TeV by the CMS experiment in 2011. The data sample corresponds to an integrated luminosity of approximately 5 fb− 1. The event yields observed in the signal regions are consistent with predictions of the standard model backgrounds, and upper limits on the cross section times branching fraction for a resonance decaying to dileptons are extracted from a shape analysis of the dilepton invariant mass ...
The performance of the Local Trigger based on the drift-tube system of the CMS experiment has bee... more The performance of the Local Trigger based on the drift-tube system of the CMS experiment has been studied using muons from cosmic ray events collected during the commissioning of the detector in 2008. The properties of the system are extensively tested and compared with the simulation. The effect of the random arrival time of the cosmic rays on the trigger performance is reported, and the results are compared with the design expectations for proton-proton collisions and with previous measurements obtained with ...
A search for a Higgs boson in the four-lepton decay channel H! ZZ, with each Z boson decaying to ... more A search for a Higgs boson in the four-lepton decay channel H! ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range of 110< mH< 600 GeV. The analysis uses data corresponding to an integrated luminosity of 4: 7 fbÀ1 recorded by the CMS detector in pp collisions at ffiffiffi sp ¼ 7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m4 '> 100 GeV (with 13 below 160 GeV), while 67: 1 Æ 6: 0 (9: 5 Æ 1: 3) events are expected ...
2: 76 TeV with the CMS detector at the LHC, in a 7: 2 bÀ1 data sample. The number of opposite-sig... more 2: 76 TeV with the CMS detector at the LHC, in a 7: 2 bÀ1 data sample. The number of opposite-sign muon pairs observed in the 60–120 GeV= c 2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of ½33: 8 Æ 5: 5ðstatÞ Æ 4: 4ðsystÞ Â 10 À8, in the jyj< 2: 0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.
A measurement of the double-differential inclusive dijet production cross section in proton–proto... more A measurement of the double-differential inclusive dijet production cross section in proton–proton collisions at View the MathML source is presented as a function of the dijet invariant mass and jet rapidity. The data correspond to an integrated luminosity of 36 pb− 1, recorded with the CMS detector at the LHC. The measurement covers the dijet mass range 0.2 TeV to 3.5 TeV and jet rapidities up to| y|= 2.5. It is found to be in good agreement with next-to-leading-order QCD predictions.
A search for physics beyond the standard model in events with at least three leptons and any numb... more A search for physics beyond the standard model in events with at least three leptons and any number of jets is presented. The data sample corresponds to 35 pb− 1 of integrated luminosity in pp collisions at s= 7 TeV collected by the CMS experiment at the LHC. A number of exclusive multileptonic channels are investigated and standard model backgrounds are suppressed by requiring sufficient missing transverse energy, invariant mass inconsistent with that of the Z boson, or high jet activity. Control samples in data are ...
A search for narrow resonances at high mass in the dimuon and dielectron channels has been perfor... more A search for narrow resonances at high mass in the dimuon and dielectron channels has been performed by the CMS experiment at the CERN LHC, using pp collision data recorded at TeV. The event samples correspond to integrated luminosities of 40 pb− 1 in the dimuon channel and 35 pb− 1 in the dielectron channel. Heavy dilepton resonances are predicted in theoretical models with extra gauge bosons (Z′) or as Kaluza-Klein graviton excitations (G KK) in the Randall-Sundrum model. Upper limits on the inclusive ...
A measurement of the underlying activity in events with a jet of transverse momentum in the sever... more A measurement of the underlying activity in events with a jet of transverse momentum in the several GeV region is performed in proton-proton collisions at and 7 TeV, using data collected by the CMS experiment at the LHC. The production of charged particles with pseudorapidity| η|< 2 and transverse momentum p T> 0. 5 GeV/c is studied in the azimuthal region transverse to that of the leading set of charged particles forming a track-jet. A significant growth of the average multiplicity and scalar-p T sum of the particles in the ...
Journal of physics. G, Nuclear and particle physics, 2007
DI-fusion, le Dépôt institutionnel numérique de l'ULB, est l'outil de référencementde l... more DI-fusion, le Dépôt institutionnel numérique de l'ULB, est l'outil de référencementde la production scientifique de l'ULB.L'interface de recherche DI-fusion permet de consulter les publications des chercheurs de l'ULB et les thèses qui y ont été défendues.
Combined results are reported from searches for the standard model Higgs boson in proton–proton c... more Combined results are reported from searches for the standard model Higgs boson in proton–proton collisions at s= 7 TeV in five Higgs boson decay modes: γγ, bb, ττ, WW, and ZZ. The explored Higgs boson mass range is 110–600 GeV. The analysed data correspond to an integrated luminosity of 4.6–4.8 fb− 1. The expected excluded mass range in the absence of the standard model Higgs boson is 118–543 GeV at 95% CL. The observed results exclude the standard model Higgs boson in the mass range 127–600 GeV at 95% CL, and in the ...
The top quark is pair-produced in pp collisions through quark-antiquark annihilation and gluon-gl... more The top quark is pair-produced in pp collisions through quark-antiquark annihilation and gluon-gluon fusion. The measurement of the tt cross section tests the QCD calculations for the pair production of a massive colored triplet. These calculations have been performed in perturbation theory to next-to-leading-order [1, 2]. Recent work on corrections for soft gluon emission shows that their effect on the cross section is small, and that they reduce the theoretical uncertainty arising from the choice of renormalization and factorization scales ...
Page 1. EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/2011-024 2011/03/18 CMS-EWK-... more Page 1. EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/2011-024 2011/03/18 CMS-EWK-10-006 Measurement of the Lepton Charge Asymmetry in Inclusive W Production in pp Collisions at √ s = 7 TeV The CMS Collaboration ∗ Abstract ...
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