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Measurement of b Hadron Lifetimes in Exclusive Decays Containing a J/ψ in pp̅ Collisions at √s=1.96  TeV

  • Aaltonen, T.
  • Álvarez González, B.
  • Casal, Bruno
  • Cuevas, Javier
  • Gómez, G.
  • Palencia, Enrique
  • Rodrigo, Teresa
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • Zucchelli, S.
  • Cabrera, Susana
  • Cuenca Almenar, Cristóbal
  • Ruiz Jimeno, Alberto
  • CDF Collaboration
8 páginas, 2 figuras, 1 tabla.-- Grupo de trabajo: CDF Collaboration.-- PACS numbers: 13.25.Hw, 13.30.Eg, 14.20.Mr, 14.40.Nd.-- et al., We report on a measurement of b-hadron lifetimes in the fully reconstructed decay modes B+→J/ψK+, B0→J/ψK*(892)0, B0→J/ψKs0, and Λb0→J/ψΛ0 using data corresponding to an integrated luminosity of 4.3  fb-1, collected by the CDF II detector at the Fermilab Tevatron. The measured lifetimes are τ(B+)=[1.639±0.009(stat)±0.009(syst)]  ps, τ(B0)=[1.507±0.010(stat)±0.008(syst)]  ps, and τ(Λb0)=[1.537±0.045(stat)±0.014(syst)]  ps. The lifetime ratios are τ(B+)/τ(B0)=[1.088±0.009(stat)±0.004(syst)] and τ(Λb0)/τ(B0)=[1.020±0.030(stat)±0.008(syst)]. These are the most precise determinations of these quantities from a single experiment., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fu¨r Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, U.K.; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland., Peer reviewed
Proyecto:


Measurement of the B- lifetime using a simulation free approach for trigger bias correction

  • Aaltonen, T.
  • Zucchelli, S.
  • Cabrera, Susana
  • Cuenca Almenar, Cristóbal
  • Álvarez González, B.
  • Casal, Bruno
  • Cuevas, Javier
  • Gómez, G.
  • Rodrigo, Teresa
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
30 páginas, 12 figuras, 8 tablas.-- PACS numbers: 14.40Nd;13.25.Hw;29.85.Fj.-- CDF Collaboration: et al., The collection of a large number of B-hadron decays to hadronic final states at the CDF II Detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper-decay-time distribution. A lifetime measurement must correct for this bias, and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper, we present an analytic method for bias correction without using simulation, thereby removing any uncertainty due to the differences between data and simulation. This method is presented in the form of a measurement of the lifetime of the B- using the mode B-→D0π-. The B- lifetime is measured as τB-=1.663±0.023±0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium f¨ur Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/ CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland., Peer reviewed
Proyecto:


Observation of long-range, near-side angular correlations in proton-proton collisions at the LHC

  • Khachatryan, V.
  • Cabrillo, I. J.
  • Cabrillo, I. J.
  • Chuang, S. H.
  • Fernández, M.
  • Gómez, G.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Piedra, Jonatan
  • Rodrigo, Teresa
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • Weinberger, M.
38 páginas, 10 figuras, 4 tablas.-- This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.-- CMS Collaboration: et al., Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center-of-mass energies of 0.9, 2.36, and 7 TeV are presented, using data collected with the CMS detector over a broad range of pseudorapidity (η) and azimuthal angle (ϕ). Short-range correlations in Δη, which are studied in minimum bias events, are characterized using a simple “independent cluster” parametrization in order to quantify their strength (cluster size) and their extent in η (cluster decay width). Long-range azimuthal correlations are studied differentially as a function of charged particle multiplicity and particle transverse momentum using a 980 nb−1 data set at 7 TeV. In high multiplicity events, a pronounced structure emerges in the two-dimensional correlation function for particle pairs with intermediate p T of 1–3 GeV/c, 2.0 < |Δη| < 4.8 and Δϕ ≈ 0. This is the first observation of such a long-range, near-side feature in two-particle correlation functions in pp or p[`(p)]ppcollisions., We thank the technical and administrative sta at CERN and other CMS institutes. This work was supported by the Austrian Federal Ministry of Science and Research; the Belgium Fonds de la Recherche Scienti que, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport; the Research Promotion Foundation, Cyprus; the Estonian Academy of Sciences and NICPB; the Academy of Finland, Finnish Ministry of Education, and Helsinki Institute of Physics; the Institut National de Physique Nucl eaire et de Physique des Particules / CNRS, and Commissariat a l' Energie Atomique, France; the Bundesministerium f ur Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scienti c Research Foundation, and National O ce for Research and Technology, Hungary; the Department of Atomic Energy, and Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Pakistan Atomic Energy Commission; the State Commission for Scienti c Research, Poland; the Funda c~ao para a Ci^encia e a Tecnologia, Portugal; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); the Ministry of Science and Technologies of the Russian Federation, and Russian Ministry of Atomic Energy; the Ministry of Science and Technological Development of Serbia; the Ministerio de Ciencia e Innovaci on, and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Scienti c and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, UK; the US Department of Energy, and the US National Science Foundation. Individuals have received support from the Marie-Curie IEF program (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; and the Associazione per lo Sviluppo Scienti co e Tecnologico del Piemonte (Italy)., Peer reviewed
Proyecto:


Measurement of d sigma/dy of Drell-Yan e(+)e(-) pairs in the Z mass region from p(p)over-bar collisions at root s=1.96 TeV

  • Aaltonen, T.
  • Cabrera, Susana
  • Cuenca Almenar, Cristóbal
  • Álvarez González, B.
  • Casal, Bruno
  • Cuevas, Javier
  • Gómez, G.
  • Rodrigo, Teresa
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
8 páginas10 figuras, 3 tablas.-- El Pdf del artículo es la versión pre-print: 0908.3914v4.-- CDF Collaboration: et al., We report on a CDF measurement of the total cross section and rapidity distribution, d sigma/dy, for gamma*/Z -> e(+)e(-) events in the Z boson mass region (66 < M(ee) < 116 GeV/c(2)) produced in p (p) over bar collisions at root s = 1.96 TeV with 2.1 fb(-1) of integrated luminosity. The measured cross section of 257 +/- 16 pb and d sigma/dy distribution are compared with Next-to-Leading-Order (NLO) and Next-to-Next-to-Leading-Order (NNLO) QCD theory predictions with CTEQ and MRST/MSTW parton distribution functions (PDFs). There is good agreement between the experimental total cross section and d sigma/dy measurements with theoretical calculations with the most recent NNLO PDFs., We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the US Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium fur Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovacion, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland. We also thank Robert Thorne for valuable discussions., Peer reviewed
Proyecto:


Search for s-channel single-top-quark production in events with missing energy plus jets in pp̅ collisions at √s=1.96TeV

  • Aaltonen, T.
  • Casal, Bruno
  • Cuevas, Javier
  • Gómez, G.
  • Palencia, Enrique
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vilar, Rocío
  • Vizán, J.
  • CDF Collaboration
The first search for single-top-quark production from the exchange of an s-channel virtual W boson using events with an imbalance in the total transverse energy, b-tagged jets, and no identified leptons is presented. Assuming the electroweak production of top quarks of mass 172.5GeV/c2 in the s channel, a cross section of 1.12-0.57+0.61 (stat+syst) pb with a significance of 1.9 standard deviations is measured. This measurement is combined with the result obtained from events with an imbalance in total transverse momentum, b-tagged jets, and exactly one identified lepton, yielding a cross section of 1.36-0.32+0.37 (stat+syst) pb, with a significance of 4.2 standard deviations. © 2014 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC); and the EU community Marie Curie Fellowship Contract No. 302103., Peer Reviewed
Proyecto:


Studies of jet mass in dijet and W/Z + jet events

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Felcini, Marta
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
Open Access: This article is distributed under the terms of the Creative Commons Attribution License.-- et al., Invariant mass spectra for jets reconstructed using the anti-k T and CambridgeAachen algorithms are studied for different jet >grooming> techniques in data corresponding to an integrated luminosity of 5 fb-1, recorded with the CMS detector in proton-proton collisions at the LHC at a center-of-mass energy of 7 TeV. Leading-order QCD predictions for inclusive dijet and W/Z+jet production combined with parton-shower Monte Carlo models are found to agree overall with the data, and the agreement improves with the implementation of jet grooming methods used to distinguish merged jets of large transverse momentum from softer QCD gluon radiation., We acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: the Austrian Federal Ministry of Science and Research; the Belgian Fonds de la Recherche Scientifique, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies(CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Recurrent financing contract SF0690030s09 and European Regional Development Fund, Estonia; the Academy of Finland, Finnish Ministry of Education and Culture, and Helsinki Institute of Physics; the Institut National de Physique Nucléaire et de Physique des Particules/CNRS, and Commissariat à l’Énergie Atomique et aux Énergies Alternatives/CEA, France; the Bundesministerium für Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scientific Research Foundation, and National Office for Research and Technology, Hungary; the Department of Atomic Energy and the Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Science and Innovation, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Fundação para a Ciência e a Tecnologia, Portugal; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); the Ministry of Education and Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic Research; the Ministry of Science and Technological Development of Serbia; the Secretaría de Estado de Investigación, Desarrollo e Innovación and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Scientific and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, UK; the US Department of Energy, and the US National Science Foundation. Individuals have received support from the Marie-Curie programme and the European Research Council (European Union); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Austrian Science Fund (FWF); the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWTBelgium); the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); the HOMING PLUS programme of Foundation for Polish Science, cofinanced from European Union, Regional Development Fund., Peer Reviewed
Proyecto:


Search for supersymmetry in pp collisions at √s = 8 TeV in events with a single lepton, large jet multiplicity, and multiple b jets

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Piedra, Jonatan
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
This is an open access article under the CC BY license.-- et al., Results are reported from a search for supersymmetry in pp collisions at a center-of-mass energy of 8 TeV, based on events with a single isolated lepton (electron or muon) and multiple jets, at least two of which are identified as b jets. The data sample corresponds to an integrated luminosity of 19.3 fb-1recorded by the CMS experiment at the LHC in 2012. The search is motivated by supersymmetric models that involve strong-production processes and cascade decays of new particles. The resulting final states contain multiple jets as well as missing transverse momentum from weakly interacting particles. The event yields, observed across several kinematic regions, are consistent with the expectations from standard model processes. The results are interpreted in the context of simplified supersymmetric scenarios with pair production of gluinos, where each gluino decays to a top quark-antiquark pair and the lightest neutralino. For the case of decays via virtual top squarks, gluinos with a mass smaller than 1.26 TeV are excluded for low neutralino masses. © 2014 The Authors., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)., Funded by SCOAP3., Peer Reviewed
Proyecto:


Search for the standard model Higgs boson produced in association with a W or a Z boson and decaying to bottom quarks

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Piedra, Jonatan
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
A search for the standard model Higgs boson (H) decaying to bb̄ when produced in association with a weak vector boson (V) is reported for the following channels: W(μν)H, W(eν)H, W(τν)H, Z(μμ)H, Z(ee)H, and Z(νν)H. The search is performed in data samples corresponding to integrated luminosities of up to 5.1 inverse femtobarns at √s=7 TeV and up to 18.9 fb-1 at √s=8 TeV, recorded by the CMS experiment at the LHC. An excess of events is observed above the expected background with a local significance of 2.1 standard deviations for a Higgs boson mass of 125 GeV, consistent with the expectation from the production of the standard model Higgs boson. The signal strength corresponding to this excess, relative to that of the standard model Higgs boson, is 1.0±0.5., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie programme and the European Research Council and EPLANET(EuropeanUnion); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dansl’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschapen Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports(MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo(Torino); the HOMINGPLUS programme of Foundation for PolishScience, cofinanced by EU,Re-gional Development Fund; and the Thalis and Aristeia programmes cofinanced byEU-ESFand the Greek NSRF., Peer Reviewed
Proyecto:


Search for top-quark partners with charge 5/3 in the same-sign dilepton final state

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Piedra, Jonatan
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
A search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5fb-1 and was collected at s=8TeV by the CMS experiment. No significant excess is observed in the data above the expected background, and the existence of top-quark partners with masses below 800 GeV is excluded at a 95% confidence level, assuming they decay exclusively to tW. This is the first limit on these particles from the LHC, and it is significantly more restrictive than previous limits. © 2014 CERN, for the CMS Collaboration., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)., Peer Reviewed
Proyecto:


Search for top squark and higgsino production using diphoton Higgs boson decays

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Piedra, Jonatan
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
This article is available under the terms of the Creative Commons Attribution 3.0 License.-- et al., Results are presented of a search for a >natural> supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7fb-1 of proton-proton collision data at s=8TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass. © 2014 CERN, for the CMS Collaboration., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)., Peer Reviewed
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