The matter - anti matter asymmetry observed in the universe today still lacks a quantitative explanation. One possibility that could contribute to the observed state could be a violation of the combined Charge-, Partiy- and Timesymmetries (CPT). To test if the CPT symmetry is broken the ASACUSA collaboration (Atomic Spectroscopy And Collisions Using Slow Antiprotons) at the CERN AD (Antiproton Decelerator) tries to produce a low temperature beam of antihydrogen - the most simple atomic system built only of anti particles. The ground state hyperfine splitting of hydrogen is one of the most precisely determined quantities in physics. Therefore it follows naturally to test CPT invariance by comparing the ground state hyperfine splitting of hydrogen and antihydrogen at zero B field. This contribution will focus on presenting the current state of the fully assembled spectroscopy beamline, including a field-ioniser chamber, a strip-line resonator microwave cavity, a super conducting sextupole magnet and a detector for counting antihydrogen annihilations. We will put a spotlight on the performance of the beamline and on the detection part of the spectrometer. Our spectroscopy apparatus was tested with a beam of cold hydrogen and these tests lead to a measurement of the GS-HFS of hydrogen whose precision is in good agreement with simulation. The newly developed detector is composed of a position sensitive Bismutgermanat (BGO) disc in the centre and a two layer hodoscope made of plastic scintillators that is read via silicon photo multipliers (SiPM) with self developed frontend electronics. In addition, our first preliminary results of the detector performance with the fully assembled beamline from the 2014 beamtime at CERN are discussed. ; Grant-in-Aid for Specially Promoted Research (No. 24000008) of the Japan Society for the Promotion of Science (JSPS), and Pioneering Project of RIKEN, European Research Council under European Union's Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement (291242), the ...
Austrian de la Recherche Scientifique ; Fonds voor Wetenschappelijk Onderzoek ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Bulgarian Ministry of Education and Science ; CERN ; Chinese Academy of Sciences ; Ministry of Science and Technology ; National Natural Science Foundation of China ; Colombian Funding Agency (COLCIENCIAS) ; Croatian Ministry of Science, Education and Sport ; Research Promotion Foundation, Cyprus ; Ministry of Education and Research ; European Regional Development Fund, Estonia ; Academy of Finland ; Finnish Ministry of Education and Culture ; Helsinki Institute of Physics ; Institut National de Physique Nucleaire et de Physique des Particules / CNRS ; Commissariat a l'Energie Atomique et aux Energies Alternatives / CEA, France ; Bundesministerium fur Bildung und Forschung ; Deutsche Forschungsgemeinschaft ; Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany ; General Secretariat for Research and Technology, Greece ; National Scientific Research Foundation ; National Office for Research and Technology, Hungary ; Department of Atomic Energy ; Department of Science and Technology, India ; Institute for Studies in Theoretical Physics and Mathematics, Iran ; Science Foundation, Ireland ; Istituto Nazionale di Fisica Nucleare, Italy ; Korean Ministry of Education, Science and Technology ; World Class University program of NRF, Republic of Korea ; Lithuanian Academy of Sciences ; CINVESTAV ; CONACYT ; SEP ; UASLP-FAI ; Ministry of Business, Innovation and Employment, New Zealand ; Pakistan Atomic Energy Commission ; Ministry of Science and Higher Education ; National Science Centre, Poland ; Fundacao para a Ciencia e a Tecnologia, Portugal ; JINR, Dubna ; Ministry of Education and Science of the Russian Federation ; Federal Agency of Atomic Energy of the Russian Federation ; Russian Academy of Sciences ; Russian Foundation for Basic Research ; Ministry of Education, Science and Technological Development of Serbia ; Secretaria de Estado de Investigacion, Desarrollo e Innovacion ; Programa Consolider-Ingenio, Spain ; ETH Board ; ETH Zurich ; PSI ; SNF ; UniZH ; Canton Zurich ; SER ; National Science Council, Taipei ; Thailand Center of Excellence in Physics ; Institute for the Promotion of Teaching Science and Technology of Thailand ; Special Task Force for Activating Research ; National Science and Technology Development Agency of Thailand ; Scientific and Technical Research Council of Turkey ; Turkish Atomic Energy Authority ; Science and Technology Facilities Council, U.K. ; US Department of Energy ; US National Science Foundation ; Marie-Curie programme ; European Research Council ; EPLANET (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation for Polish Science ; EU, Regional Development Fund ; Thalis and Aristeia programmes ; EU-ESF ; Greek NSRF ; Ministry of Education and ResearchSF0690030s09 ; A measurement of the Z gamma -> nu(nu) over bar gamma cross section in pp collisions at root s = 7 TeV is presented, using data corresponding to an integrated luminosity of 5.0 fb(-1) collected with the CMS detector. This measurement is based on the observation of events with an imbalance of transverse energy in excess of 130 GeV and a single photon in the absolute pseudorapidity range vertical bar eta vertical bar nugamma production cross section is measured to be 21.1 +/- 4.2(stat.)+/- 4.3(syst.)+/- 0.5(lum.)fb, which agrees with the standard model prediction of 21.9 +/- 1.1 fb. The results are combined with the CMS measurement of Z gamma production in the l(+)l(-)gamma final state (where l is an electron or a muon) to yield the most stringent limits to date on triple gauge boson couplings. vertical bar h(3)(Z)vertical bar < 2.7 x 10(-3), vertical bar h(4)(Z)vertical bar < 1.3 x 10(-5) for ZZ gamma and vertical bar h(3)(gamma)vertical bar < 2.9 x 10(-3), vertical bar h(4)(gamma)vertical bar < 1.5 x 10(-5) for Z gamma gamma couplings.
BMWF (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MES (Bulgaria) ; CERN (China) ; CAS (China) ; MoST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; RPF (Cyprus) ; MoER (Estonia) ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; OTKA (Hungary) ; NKTH (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; NRF (Republic of Korea) ; WCU (Republic of Korea) ; LAS (Lithuania) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MBIE (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Dubna) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; MESTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; STAR (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; STFC (United Kingdom) ; DOE (USA) ; NSF (USA) ; Marie-Curie programme ; European Research Council (European Union) ; EPLANET (European Union) ; Leventis Foundation ; A.P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation For Polish Science - EU, Regional Development Fund ; EU-ESF ; Greek NSRF ; MoER (Estonia)SF0690030s09 ; CEA (France)CNRS/IN2P3 ; A peaking structure in the J/psi phi mass spectrum near threshold is observed in B-+/- -> J/psi phi K-+/- decays, produced in pp collisions at root s = 7 TeV collected with the CMS detector at the LHC. The data sample, selected on the basis of the dimuon decay mode of the J/psi, corresponds to an integrated luminosity of 5.2 fb(-1). Fitting the structure to an S-wave relativistic Breit-Wigner lineshape above a three-body phase-space nonresonant component gives a signal statistical significance exceeding five standard deviations. The fitted mass and width values are m = 4148.0 +/- 2.4 (stat.) +/- 6.3 (syst.) MeV and Gamma = 28(-11)(+15) (stat.) +/- 19 (syst.) MeV, respectively. Evidence for an additional peaking structure at higher J/psi phi mass is also reported. (C) 2014 The Authors. Published by Elsevier B.V.
BMWF (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MEYS (Bulgaria) ; CERN ; CAS (China) ; MoST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; RPF (Cyprus) ; MoER ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; CNRS/IN2P3 (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; OTKA (Hungary) ; NKTH (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; NRF (Republic of Korea) ; WCU (Republic of Korea) ; LAS (Lithuania) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MSI (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Armenia) ; JINR (Belarus) ; JINR (Georgia) ; JINR (Ukraine) ; JINR (Uzbekistan) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; MSTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; STFC (United Kingdom) ; DOE (USA) ; NSF (USA) ; Marie-Curie programme ; European Research Council ; EPLANET (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation for Polish Science ; EU, Regional Development Fund ; Thalis programme ; Aristeia programme ; EU-ESF ; Greek NSRF ; MoERSF0690030s09 ; A measurement of W+W- production in pp collisions at is presented. The data were collected with the CMS detector at the LHC, and correspond to an integrated luminosity of 4.92 +/- 0.11 fb(-1). The W+W- candidates consist of two oppositely charged leptons, electrons or muons, accompanied by large missing transverse energy. The W+W- production cross section is measured to be 52.4 +/- 2.0 (stat.)+/- 4.5 (syst.)+/- 1.2 (lum.) pb. This measurement is consistent with the standard model prediction of 47.0 +/- 2.0 pb at next-to-leading order. Stringent limits on the WW gamma and WWZ anomalous triple gauge-boson couplings are set.
FMSR (Austria) ; Fonds de la Recherche Scientifique (FNRS) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MES (Bulgaria) ; Organisation Européenne pour la Recherche Nucléaire (CERN) ; CAS ; MoST ; National Natural Science Foundation of China (NSFC) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; Research Promotion Foundation (RPF) ; MoER ; European Regional Development Fund (ERDF) ; Academy of Finland ; MEC ; Helsinki Institute of Physics (HIP) ; CEA ; Institut national de physique nucléaire et de physique des particules (IN2P3/CNRS) ; Bundesministerium für Bildung und Forschung (BMBF) ; Deutsche Forschungsgemeinschaft (DFG) ; HGF (Germany) ; General Secretariat for Research and Technology (GSRT) ; OTKA ; NKTH (Hungary) ; DAE ; Department of Science and Technology (DST) - India ; Science Foundation Ireland (SFI) ; Istituto Nazionale di Fisica Nucleare (INFN) ; NRF ; WCU (Korea) ; LAS (Lithuania) ; Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV) ; Consejo Nacional de Ciencia y Tecnología (CONACYT) ; SEP ; UASLP-FAI (Mexico) ; MSI (New Zealand) ; Pakistan Atomic Energy Commission (PAEC) ; MSHE ; NSC (Poland) ; Fundação para a Ciência e a Tecnologia (FCT) ; Joint Institute for Nuclear Research (JINR) ; MON ; Rosatom State Atomic Energy Corporation (ROSATOM) ; RAS ; Russian Foundation for Basic Research (RFBR) ; Ministry of Science and Technological Development (MSTD) - Serbia ; MICINN ; Centro Nacional de Física de Partículas, Astropartículas y Nuclear (CPAN) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; Scientific and Technological Research Council of Turkey (TUBITAK) ; Türkiye Atom Enerjisi Kurumu (TAEK) ; Science and Technology Facilities Council (STFC) ; Department of Energy (DOE) ; National Science Foundation (NSF) - USA ; Marie-Curie programme ; European Research Council (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT) ; Council of Scientific and Industrial Research (CSIR) - India ; HOMING PLUS programme of Foundation for Polish Science ; European Union ; MoER: SF0690030s09 ; A search for a new heavy gauge boson W' decaying to an electron or muon, plus a low mass neutrino, is presented. This study uses data corresponding to an integrated luminosity of 5.0 fb(-1), collected using the CMS detector in pp collisions at a centre-of-mass energy of 7TeV at the LHC. Events containing a single electron or muon and missing transverse momentum are analyzed. No significant excess of events above the standard model expectation is found in the transverse mass distribution of the lepton-neutrino system, and upper limits for cross sections above different transverse mass thresholds are presented. Mass exclusion limits at 95% CL for a range of W' models are determined, including a limit of 2.5TeV for right-handed W' bosons with standard-model-like couplings and limits of 2.43-2.63 TeV for left-handed W' bosons, taking into account their interference with the standard model W boson. Exclusion limits have also been set on Kaluza-Klein W-KK states in the framework of split universal extra dimensions.
Austrian Federal Ministry of Science and Research ; Belgium Fonds de la Recherche Scientifique ; Fonds voor Wetenschappelijk Onderzoek ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Bulgarian Ministry of Education and Science ; Organisation Européenne pour la Recherche Nucléaire (CERN) ; National Natural Science Foundation of China (NSFC) ; Colombian Funding Agency (COLCIENCIAS) ; Croatian Ministry of Science, Education and Sport ; Research Promotion Foundation (RPF) ; Ministry of Education and Research ; European Regional Development Fund (ERDF) ; Academy of Finland ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA) ; Bundesministerium für Bildung und Forschung (BMBF) ; General Secretariat for Research and Technology (GSRT) ; National Scientific Research Foundation, and National Office for Research and Technology, Hungary ; Department of Science and Technology (DST) - India ; Institute for Studies in Theoretical Physics and Mathematics, Iran ; Science Foundation Ireland (SFI) ; Istituto Nazionale di Fisica Nucleare (INFN) ; National Research Foundation of Korea (NRF) ; Lithuanian Academy of Sciences ; Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV) ; Consejo Nacional de Ciencia y Tecnología (CONACYT) ; SEP ; UASLP-FAI ; Pakistan Atomic Energy Commission (PAEC) ; Ministry of Science and Higher Education and the National Science Centre, Poland ; Fundaccao para a Ciência e a Tecnologia, Portugal ; Joint Institute for Nuclear Research (JINR) ; Russian Foundation for Basic Research (RFBR) ; Ministry of Science and Technological Development of Serbia ; Ministerio de Ciência e Innovacion, Spain ; ETH Board ; ETH Zurich ; PSI ; SNF ; UniZH ; Canton Zurich ; SER ; National Science Council, Taipei ; Science and Technology Facilities Council (STFC) ; US Department of Energy, and the US National Science Foundation ; European Research Council (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT) ; Council of Scientific and Industrial Research (CSIR) - India ; Foundation for Polish Science ; European Union ; MoER: SF0690030s09 ; A search for the rare decays B-S(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-) performed in pp collisions at root s = 7 TeV, with a data sample corresponding to an integrated luminosity of 5 fb(-1) collected by the CMS experiment at the LHC. In both decays, the number of events observed after all selection requirements is consistent with the expectation from background plus standard model signal predictions. The resulting upper limits on the branching fractions are B(B-S(0) -> mu(+)mu(-)) mu(+)mu(-) ) < 1.8 x 10(-9) at 95% confidence level.
FMSR (Austria) ; Fonds de la Recherche Scientifique (FNRS) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MES (Bulgaria) ; Organisation Européenne pour la Recherche Nucléaire (CERN) ; Chinese Academy of Sciences (CAS) ; MoST (China) ; National Natural Science Foundation of China (NSFC) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; Research Promotion Foundation (RPF) ; MoER ; European Regional Development Fund (ERDF) ; Academy of Finland ; MEC ; Helsinki Institute of Physics (HIP) ; CEA ; Institut national de physique nucléaire et de physique des particules (IN2P3/CNRS) ; Bundesministerium für Bildung und Forschung (BMBF) ; Deutsche Forschungsgemeinschaft (DFG) ; HGF (Germany) ; General Secretariat for Research and Technology (GSRT) ; Hungarian Scientific Research Fund (OTKA) ; NKTH (Hungary) ; Department of Atomic Energy (DAE) - India ; Department of Science and Technology (DST) - India ; Institute for Research in Fundamental Sciences (IPM) ; Science Foundation Ireland (SFI) ; Istituto Nazionale di Fisica Nucleare (INFN) ; NRF ; WCU (Korea) ; LAS (Lithuania) ; Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV) ; Consejo Nacional de Ciencia y Tecnología (CONACYT) ; SEP (Mexico) ; SEP, and UASLP-FAI (Mexico) ; MSI (New Zealand) ; Pakistan Atomic Energy Commission (PAEC) ; MSHE (Poland) ; NSC (Poland) ; Fundação para a Ciência e a Tecnologia (FCT) ; Joint Institute for Nuclear Research (JINR) ; MON (Russia) ; Rosatom State Atomic Energy Corporation (ROSATOM) ; RAS (Russia) ; Russian Foundation for Basic Research (RFBR) ; Ministry of Science and Technological Development (MSTD) - Serbia ; MICINN (Spain) ; Centro Nacional de Física de Partículas, Astropartículas y Nuclear (CPAN) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; Scientific and Technological Research Council of Turkey (TUBITAK) ; Türkiye Atom Enerjisi Kurumu (TAEK) ; Science and Technology Facilities Council (STFC) ; Department of Energy (DOE) and National Science Foundation (NSF) - USA ; Marie-Curie programme ; European Research Council (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT) ; Council of Scientific and Industrial Research (CSIR) - India ; HOMING PLUS programme of Foundation for Polish Science ; European Union, Regional Development Fund ; MoER: SF0690030s09 ; Jet fragmentation in pp and PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair was studied using data collected with the CMS detector at the LHC. Fragmentation functions are constructed using charged-particle tracks with transverse momenta p(T) > 4 GeV/c for dijet events with a leading jet of p(T) > 100 GeV/c. The fragmentation functions in PbPb events are compared to those in pp data as a function of collision centrality, as well as dijet-p(T) imbalance. Special emphasis is placed on the most central PbPb events including dijets with unbalanced momentum, indicative of energy loss of the hard scattered parent partons. The fragmentation patterns for both the leading and subleading jets in PbPb collisions agree with those seen in pp data at 2.76 TeV. The results provide evidence that, despite the large parton energy loss observed in PbPb collisions, the partition of the remaining momentum within the jet cone into high-p(T) particles is not strongly modified in comparison to that observed for jets in vacuum.
Austrian Federal Ministry of Science and Research ; Austrian Science Fund ; Belgian Fonds de la Recherche Scientifique ; Fonds voor Wetenschappelijk Onderzoek ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Bulgarian Ministry of Education, Youth and Science ; CERN ; Chinese Academy of Sciences ; Ministry of Science and Technology ; National Natural Science Foundation of China ; Colombian Funding Agency (COLCIENCIAS) ; Croatian Ministry of Science, Education and Sport ; Research Promotion Foundation, Cyprus ; Ministry of Education and Research ; European Regional Development Fund, Estonia ; Academy of Finland ; Finnish Ministry of Education and Culture ; Helsinki Institute of Physics ; Institut National de Physique Nucleaire et de Physique des Particules / CNRS ; Commissariat a l'Energie Atomique et aux Energies Alternatives / CEA, France ; Bundesministerium fur Bildung und Forschung ; Deutsche Forschungsgemeinschaft ; Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany ; General Secretariat for Research and Technology, Greece ; National Scientific Research Foundation ; National Office for Research and Technology, Hungary ; Department of Atomic Energy ; Department of Science and Technology, India ; Institute for Studies in Theoretical Physics and Mathematics, Iran ; Science Foundation, Ireland ; Istituto Nazionale di Fisica Nucleare, Italy ; Korean Ministry of Education, Science and Technology ; World Class University program of NRF, Republic of Korea ; Lithuanian Academy of Sciences ; CINVESTAV ; CONACYT ; SEP ; UASLP-FAI ; Ministry of Science and Innovation, New Zealand ; Pakistan Atomic Energy Commission ; Ministry of Science and Higher Education ; National Science Centre, Poland ; Fundacao para a Ciencia e a Tecnologia, Portugal ; JINR (Armenia) ; JINR (Belarus) ; JINR (Georgia) ; JINR (Ukraine) ; JINR (Uzbekistan) ; Ministry of Education and Science of the Russian Federation ; Federal Agency of Atomic Energy of the Russian Federation ; Russian Academy of Sciences ; Russian Foundation for Basic Research ; Ministry of Science and Technological Development of Serbia ; Secretaria de Estado de Investigacion ; Desarrollo e Innovacion and Programa Consolider-Ingenio, Spain ; ETH Board ; ETH Zurich ; PSI ; SNF ; UniZH ; Canton Zurich ; SER ; National Science Council, Taipei ; Thailand Center of Excellence in Physics ; Institute for the Promotion of Teaching Science and Technology of Thailand ; National Science and Technology Development Agency of Thailand ; Scientific and Technical Research Council of Turkey ; Turkish Atomic Energy Authority ; Science and Technology Facilities Council, U.K. ; US Department of Energy ; US National Science Foundation ; Marie-Curie programme ; European Research Council ; EPLANET (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation for Polish Science ; EU, Regional Development Fund ; Thalis programme ; Aristeia programme ; EU-ESF ; Greek NSRF ; Ministry of Education and ResearchSF0690030s09 ; A study of proton-proton collisions in which two b hadrons are produced in association with a Z boson is reported. The collisions were recorded at a centre-of-mass energy of 7 TeVwith the CMS detector at the LHC, for an integrated luminosity of 5.2 fb(-1). The b hadrons are identified by means of displaced secondary vertices, without the use of reconstructed jets, permitting the study of b-hadron pair production at small angular separation. Differential cross sections are presented as a function of the angular separation of the b hadrons and the Z boson. In addition, inclusive measurements are presented. For both the inclusive and differential studies, different ranges of Z boson momentum are considered, and each measurement is compared to the predictions from different event generators at leading-order and next-to-leading-order accuracy.
BMWF (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MEYS (Bulgaria) ; CERN (China) ; CAS (China) ; MoST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; RPF (Cyprus) ; MoER ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; CNRS/IN2P3 (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; OTKA (Hungary) ; NKTH (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; NRF (Republic of Korea) ; WCU (Republic of Korea) ; LAS (Lithuania) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MST (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; MSTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; STFC (United Kingdom) ; DOE (USA) ; NSF (USA) ; Marie-Curie programme ; European Research Council ; EPLANET (European Union) ; Leventis Foundation ; A. P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation for Polish Science ; EU, Regional Development Fund ; Thalis programme ; EU-ESF ; Greek NSRF ; Aristeia programme ; MoERSF0690030s09 ; The first measurement of the electroweak production cross section of a Z boson with two jets (Zjj) in pp collisions at root s = 7 TeV is presented, based on a data sample recorded by the CMS experiment at the LHC with an integrated luminosity of 5 fb(-1). The cross section is measured for the lljj (l = e, mu) final state in the kinematic region m(ll) > 50 GeV, m(jj) > 120 GeV, transverse momenta p(T)(j) > 25 GeV and pseudorapidity vertical bar eta(j)vertical bar < 4.0. The measurement, combining the muon and electron channels, yields sigma = 154 +/- 24 (stat.) +/- 46 (exp. syst.) +/- 27 (th. syst.) +/- 3 (lum.) fb, in agreement with the theoretical cross section. The hadronic activity, in the rapidity interval between the jets, is also measured. These results establish an important foundation for the more general study of vector boson fusion processes, of relevance for Higgs boson searches and for measurements of electroweak gauge couplings and vector boson scattering.
BMWF (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MEYS (Bulgaria) ; CERN ; CAS (China) ; MoST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; RPF (Cyprus) ; MoER (Estonia) ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; CNRS/IN2P3 (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; OTKA (Hungary) ; NKTH (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; NRF (Republic of Korea) ; WCU (Republic of Korea) ; LAS (Lithuania) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MSI (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Armenia) ; JINR (Belarus) ; JINR (Georgia) ; JINR (Ukraine) ; JINR (Uzbekistan) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; MSTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; Swiss Funding Agencies (Switzerland) ; NSC (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; STFC (United Kingdom) ; DOE (USA) ; NSF (USA) ; Marie-Curie programme (European Union) ; European Research Council (European Union) ; EPLANET (European Union) ; Leventis Foundation ; A.P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; Ministry of Education, Youth and Sports (MEYS) of Czech Republic ; Council of Science and Industrial Research, India ; Compagnia di San Paolo (Torino) ; HOMING PLUS programme of Foundation for Polish Science ; EU, Regional Development Fund ; Thalis programme ; Aristeia programme ; EU-ESF ; Greek NSRF ; MoER (Estonia)SF0690030s09 ; A measurement is presented of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section as a function of the average transverse momentum, , of the two leading jets in the event. The data sample was collected during 2011 at a proton-proton centre-of-mass energy of 7 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 5.0 fb(-1). The strong coupling constant at the scale of the Z boson mass is determined to be alpha(S)(M-Z) = 0.1148 +/- 0.0014 (exp.) +/- 0.0018 (PDF) +/- 0.0050 (theory), by comparing the ratio in the range 0.42 < 1.39 TeV to the predictions of perturbative QCD at next-to-leading order. This is the first determination of alpha(S)(M-Z) from measurements at momentum scales beyond 0.6 TeV. The predicted ratio depends only indirectly on the evolution of the parton distribution functions of the proton such that this measurement also serves as a test of the evolution of the strong coupling constant. No deviation from the expected behaviour is observed.