Published April 4, 2012 | Version Published
Journal Article Open

Measurement of isolated photon production in pp and PbPb collisions at √snn = 2.76 TeV

Abstract

Isolated photon production is measured in proton–proton and lead–lead collisions at nucleon–nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |η|<1.44 and transverse energies E_T between 20 and 80 GeV with the CMS detector at the LHC. The measured E_T spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon E_T-differential yields, scaled by the number of incoherent nucleon–nucleon collisions, is consistent with unity for all PbPb reaction centralities.

Additional Information

© 2012 CERN. Published by Elsevier B.V. This article is published Open Access at sciencedirect.com. It is distributed under the terms of the Creative Commons Attribution License 3.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited. Received 16 January 2012. Received in revised form 21 February 2012. Accepted 25 February 2012. Available online 1 March 2012. Editor: M. Doser. We wish to congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC machine. We thank the technical and administrative staff 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 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 Estonian Academy of Sciences and NICPB; 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 State Commission for Scientific Research, Poland; the Fundação para a Ciência e a Tecnologia, Portugal; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); the Ministry of Science and Technologies of the Russian Federation, the Russian Ministry of Atomic Energy and the Russian Foundation for Basic Research; the Ministry of Science and Technological Development of Serbia; the Ministerio de Ciencia 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 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 (IWT-Belgium); and the Council of Science and Industrial Research, India.

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Additional details

Identifiers

Eprint ID
31681
Resolver ID
CaltechAUTHORS:20120529-132601996

Funding

Austrian Federal Ministry of Science and Research
Belgium Fonds de la Recherche Scientifique, and Fonds voor Wetenschappelijk Onderzoek
CNPq (Brazil)
CAPES (Brazil)
FAPERJ (Brazil)
FAPESP (Brazil)
Bulgarian Ministry of Education and Science
CERN
Chinese Academy of Sciences
Ministry of Science and Technology
National Natural Science Foundation of China
COLCIENCIAS (Colombia)
Croatian Ministry of Science, Education and Sport
Research Promotion Foundation, Cyprus
Estonian Academy of Sciences and NICPB
Academy of Finland
Finnish Ministry of Education and Culture, and Helsinki Institute of Physics
Institut National de Physique Nucléaire et de Physique des Particules/CNRS
Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA) France
Bundesministerium für Bildung und Forschung and Deutsche Forschungsgemeinschaft (Germany)
Helmholtz-Gemeinschaft Deutscher Forschungszentren (Germany)
General Secretariat for Research and Technology (Greece)
National Scientific Research Foundation, and National Office for Research and Technology (Hungary)
Department of Atomic Energy and the 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 and the World Class University Program of NRF (KOREA)
Lithuanian Academy of Sciences
CINVESTAV (Mexico)
CONACyT (Mexico)
SEP and UASLP-FAI (Mexico)
Ministry of Science and Innovation, New Zealand
Pakistan Atomic Energy Commission
State Commission for Scientific Research (Poland)
Fundação para a Ciência e a Tecnologia (Portugal)
JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan)
Ministry of Science and Technologies of the Russian Federation
Russian Ministry of Atomic Energy and the Russian Foundation for Basic Research
Ministry of Science and Technological Development of Serbia
Ministerio de Ciencia e Innovacion, and Programa Consolider-Ingenio 2010, Spain
ETH Board
ETH Zurich
PSI
SNF
UniZH
Canton Zurich
SER (Switzerland)
National Science Council (Taipei)
Scientific and Technical Research Council of Turkey
Turkish Atomic Energy Authority
Science and Technology Facilities Council (UK)
Department of Energy (DOE)
NSF
Marie-Curie programme and the European Research Council (European Union)
Leventis Foundation
A. P. Sloan Foundation
Alexander von Humboldt Foundation
Belgian Federal Science Policy Office
Fonds pour la Formation à la Recherche dans l'índustrie et dans l'Ágriculture (FRIA-Belgium)
Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium)
Council of Science and Industrial Research, India

Dates

Created
2012-05-29
Created from EPrint's datestamp field
Updated
2021-11-09
Created from EPrint's last_modified field

Caltech Custom Metadata

Caltech groups
CMS@Caltech