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 vertical bar eta vertical bar < 1.44 and transverse energies E-T between 20 and 80 GeV with the CMS detector at the LHC. The measured ET 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. (C) 2012 CERN. Published by Elsevier BM. All rights reserved.

Measurement of isolated photon production in pp and PbPb collisions at root s(NN)=2.76 TeV

AMAPANE, Nicola Carlo;ARGIRO', Stefano;BOTTA, CRISTINA;CASTELLO, Roberto;COSTA, Marco;GRAZIANO, ALBERTO;MIGLIORE, Ernesto;MONACO, Vincenzo;MUSICH, MARCO;OBERTINO, Maria Margherita;PELLICCIONI, Mario;POTENZA, ALBERTO;ROMERO, Alessandra;SACCHI, Roberto;SOLA, VALENTINA;SOLANO, Ada Maria;BELLAN, Riccardo;COVARELLI, Roberto;
2012-01-01

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 vertical bar eta vertical bar < 1.44 and transverse energies E-T between 20 and 80 GeV with the CMS detector at the LHC. The measured ET 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. (C) 2012 CERN. Published by Elsevier BM. All rights reserved.
2012
710
256
277
CMS; Physics; Heavy-ions; Photons
S. Chatrchyan;V. Khachatryan;A. M. Sirunyan;A. Tumasyan;W. Adam;T. Bergauer;M. Dragicevic;J. Eroe;C. Fabjan;M. Friedl;R. Fruehwirth;V. M. ...espandi
File in questo prodotto:
File Dimensione Formato  
1-s2.0-S0370269312002286-main.pdf

Accesso aperto

Tipo di file: PDF EDITORIALE
Dimensione 752.16 kB
Formato Adobe PDF
752.16 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/102748
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 158
  • ???jsp.display-item.citation.isi??? 134
social impact