Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at root √s=0.9 and 2.36 TeV

Abstract

Measurements of inclusive charged-hadron transverse-momentum and pseudorapidity distributions are presented for proton-proton collisions at root s = 0.9 and 2.36 TeV. The data were collected with the CMS detector during the LHC commissioning in December 2009. For non-single-diffractive interactions, the average charged-hadron transverse momentum is measured to be 0.46 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 0.9 TeV and 0.50 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 2.36 TeV, for pseudorapidities between -2.4 and +2.4. At these energies, the measured pseudorapidity densities in the central region, dN(ch)/d eta vertical bar(vertical bar eta vertical bar and pp collisions. The results at 2.36 TeV represent the highest-energy measurements at a particle collider to date. ; FMSR (Austria); FNRS (Belgium)Fonds de la Recherche Scientifique - FNRS; FWO (Belgium)FWO; CNPq (Brazil)National Council for Scientific and Technological Development (CNPq); CAPES (Brazil)CAPES; FAPERJ (Brazil)Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ); FAPESP (Brazil)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); MES (Bulgaria); CERN (China); CAS (China)Chinese Academy of Sciences; MoST (China)Ministry of Science and Technology, China; NSFC (China)National Natural Science Foundation of China (NSFC); COLCIENCIAS (Colombia)Departamento Administrativo de Ciencia, Tecnologia e Innovacion Colciencias; MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland)Academy of Finland; CEA (France)French Atomic Energy Commission; CNRS/IN2P3 (France)Centre National de la Recherche Scientifique (CNRS); BMBF (Germany)Federal Ministry of Education & Research (BMBF); DFG (Germany)German Research Foundation (DFG); HGF (Germany); GSRT (Greece)Greek Ministry of Development-GSRT; OTKA (Hungary)Orszagos Tudomanyos Kutatasi Alapprogramok (OTKA); NKTH (Hungary)National Office for Research and Technology; DAE (India)Department of Atomic Energy (DAE); DST (India)Department of Science & Technology (India); IPM (Iran); SFI (Ireland)Science Foundation Ireland; INFN (Italy)Istituto Nazionale di Fisica Nucleare (INFN); NRF (Korea); LAS (Lithuania); CINVESTAV (Mexico); CONACYT (Mexico)Consejo Nacional de Ciencia y Tecnologia (CONACyT); SEP (Mexico); UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal)Portuguese Foundation for Science and Technology; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST (Russia); MAE (Russia); MSTDS (Serbia); MICINNSpanish Government; CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); TAEK (Turkey)Ministry of Energy & Natural Resources - Turkey; STFC (United Kingdom)Science & Technology Facilities Council (STFC); DOE (USA)United States Department of Energy (DOE); NSF (USA)National Science Foundation (NSF); European UnionEuropean Union (EU); Leventis Foundation; A. P. Sloan FoundationAlfred P. Sloan Foundation; Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Direct For Mathematical & Physical ScienNational Science Foundation (NSF)NSF - Directorate for Mathematical & Physical Sciences (MPS) [0757894] Funding Source: National Science Foundation; Division Of PhysicsNational Science Foundation (NSF)NSF - Directorate for Mathematical & Physical Sciences (MPS) [0757894] Funding Source: National Science Foundation; Science and Technology Facilities CouncilScience & Technology Facilities Council (STFC) [CMS, ST/I505572/1, PP/D004284/1, ST/G502412/1, PP/E002722/1, ST/I002839/1, ST/F007094/1, GRIDPP] Funding Source: researchfish ; We congratulate and express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at CERN and other CMS Institutes, and acknowledge support from: FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, 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 (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTDS (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie IEF program (European Union); the Leventis Foundation; the A. P. Sloan Foundation; and the Alexander von Humboldt Foundation. ; 2010 ; 2