Abstract
The inclusive transverse momentum (pT) distributions of primary charged particles are measured in the pseudo-rapidity range |η|<0.8 as a function of event centrality in Pb–Pb collisions at sNN=2.76 TeV with ALICE at the LHC. The data are presented in the pT range 0.15<pT<50 GeV/c for nine centrality intervals from 70–80% to 0–5%. The results in Pb–Pb are presented in terms of the nuclear modification factor RAA using a pp reference spectrum measured at the same collision energy. We observe that the suppression of high-pT particles strongly depends on event centrality. The yield is most suppressed in central collisions (0–5%) with RAA≈0.13 at pT=6–7 GeV/c. Above pT=7 GeV/c, there is a significant rise in the nuclear modification factor, which reaches RAA≈0.4 for pT>30 GeV/c. In peripheral collisions (70–80%), only moderate suppression (RAA=0.6–0.7) and a weak pT dependence is observed. The measured nuclear modification factors are compared to other measurements and model calculations.
Original language | English |
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Pages (from-to) | 52-62 |
Number of pages | 11 |
Journal | Physics Letters B |
Volume | 720 |
Issue number | 1-3 |
DOIs | |
State | Published - Mar 13 2013 |
Externally published | Yes |
Funding
The ALICE Collaboration acknowledges the following funding agencies for their support in building and running the ALICE detector: Calouste Gulbenkian Foundation from Lisbon and Swiss Fonds Kidagan , Armenia; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) , Financiadora de Estudos e Projetos (FINEP) , Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; National Natural Science Foundation of China (NSFC) , the Chinese Ministry of Education (CMOE) and the Ministry of Science and Technology of China (MSTC) ; Ministry of Education and Youth of the Czech Republic ; Danish Natural Science Research Council , the Carlsberg Foundation and the Danish National Research Foundation ; The European Research Council under the European Communityʼs Seventh Framework Programme ; Helsinki Institute of Physics and the Academy of Finland ; French CNRS-IN2P3 , the ‘Region Pays de Loire’ , ‘Region Alsace’ , ‘Region Auvergne’ and CEA , France; German BMBF and the Helmholtz Association ; General Secretariat for Research and Technology, Ministry of Development , Greece; Hungarian OTKA and National Office for Research and Technology (NKTH) ; Department of Atomic Energy and Department of Science and Technology of the Government of India ; Istituto Nazionale di Fisica Nucleare (INFN) of Italy ; MEXT Grant-in-Aid for Specially Promoted Research , Japan; Joint Institute for Nuclear Research , Dubna; National Research Foundation of Korea (NRF) ; CONACYT , DGAPA , México, ALFA-EC and the HELEN Program (High-Energy physics Latin-American–European Network) ; Stichting voor Fundamenteel Onderzoek der Materie (FOM) and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) , Netherlands; Research Council of Norway (NFR) ; Polish Ministry of Science and Higher Education ; National Authority for Scientific Research — NASR (Autoritatea Naţională pentru Cercetare Ştiinţifică — ANCS) ; Federal Agency of Science of the Ministry of Education and Science of Russian Federation , International Science and Technology Center , Russian Academy of Sciences , Russian Federal Agency of Atomic Energy , Russian Federal Agency for Science and Innovations and CERN-INTAS ; Ministry of Education of Slovakia ; Department of Science and Technology , South Africa; CIEMAT , EELA , Ministerio de Educación y Ciencia of Spain , Xunta de Galicia (Consellería de Educación) , CEADEN, Cubaenergía , Cuba, and IAEA (International Atomic Energy Agency) ; Swedish Research Council (VR) and Knut & Alice Wallenberg Foundation (KAW) ; Ukraine Ministry of Education and Science ; United Kingdom Science and Technology Facilities Council (STFC) ; The United States Department of Energy , the United States National Science Foundation , the State of Texas , and the State of Ohio .
Funders | Funder number |
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ALFA-EC | |
CERN-INTAS | |
DGAPA , México | |
Danish Natural Science Research Council | |
Department of Atomic Energy and Department of Science and Technology of the Government of India | |
European Communityʼs Seventh Framework Programme | |
Federal Agency of Science | |
General Secretariat for Research and Technology, Ministry of Development | |
Helsinki Institute of Physics | |
Ministerio de Educación y Ciencia of Spain | |
Ministry of Education and Youth of the Czech Republic | |
Ministry of Education of Slovakia | |
NFR | |
Region Auvergne’ and CEA | |
Russian Federal Agency of Atomic Energy , Russian Federal Agency for Science and Innovations | |
State of Ohio | |
Swiss Fonds Kidagan | |
United Kingdom Science and Technology Facilities Council | |
Xunta de Galicia (Consellería de Educación | |
National Science Foundation | 0968903, 0969966 |
National Science Foundation | |
U.S. Department of Energy | |
Science and Technology Facilities Council | ST/G008833/1, ST/J000140/1, ST/I003398/1, GRIDPP, ST/J000094/1 |
Science and Technology Facilities Council | |
European Research Council | |
Department of Science and Technology, Ministry of Science and Technology, India | |
Japan Society for the Promotion of Science | 20224014, 23340074, 23244055 |
Japan Society for the Promotion of Science | |
Ministry of Education, Culture, Sports, Science and Technology | |
Stichting voor Fundamenteel Onderzoek der Materie | |
Danmarks Grundforskningsfond | |
International Science and Technology Center | |
Fundação de Amparo à Pesquisa do Estado de São Paulo | |
National Natural Science Foundation of China | |
Ministry of Education of the People's Republic of China | |
Academy of Finland | CNRS-IN2P3 |
Academy of Finland | |
Bundesministerium für Bildung und Forschung | |
Russian Academy of Sciences | |
Carlsbergfondet | |
Ministry of Science and Technology of the People's Republic of China | |
Consejo Nacional de Ciencia y Tecnología | |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek | |
Ministry of Education and Science of the Russian Federation | |
Hungarian Scientific Research Fund | |
Conselho Nacional de Desenvolvimento Científico e Tecnológico | |
National Research Foundation of Korea | |
Joint Institute for Nuclear Research | |
Nemzeti Kutatási és Technológiai Hivatal | |
Instituto Nazionale di Fisica Nucleare | |
Knut och Alice Wallenbergs Stiftelse | |
Vetenskapsrådet | |
International Atomic Energy Agency | |
Ministerstwo Edukacji i Nauki | |
Financiadora de Estudos e Projetos | |
Norges Forskningsråd | |
Autoritatea Natională pentru Cercetare Stiintifică | |
Ministry of Education and Science of Ukraine | |
Helmholtz Association | |
Conseil Régional des Pays de la Loire | |
Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear | |
National Agency for Strategic Research in Medical Education |