Onset of pi(0) Suppression Studied in Cu plus Cu Collisions at s_NN) = 22.4, 62.4, and 200 GeV

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.101.162301· OSTI ID:939663

Adare, A. ^[1]; Awes, Terry C ^[2]; Cianciolo, Vince ^[2]; Efremenko, Yuri ^[3]; Read, Jr, Kenneth F ^[2]; Silvermyr, David O ^[2]; Sorensen, Soren P ^[4]; Stankus, Paul W ^[2]; Young, Glenn R ^[2]

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1. University of Colorado, Boulder
2. ORNL
3. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)
4. University of Tennessee, Knoxville (UTK)

Neutral pion transverse momentum (p{sub T}) spectra at midrapidity (|y| {le} 0.35) were measured in Cu+Cu collisions at {radical}S{sub NN} = 22.4, 62.4, and 200 GeV. Relative to {pi}{sup 0} yields in p+p collisions scaled by the number of inelastic nucleon-nucleon collisions (N{sub coll}) the {pi}{sup 0} yields for p{sub T} {ge} 2 GeV/c in central Cu+Cu collisions are suppressed at 62.4 and 200 GeV whereas an enhancement is observed at 22.4 GeV. A comparison with a jet-quenching model suggests that final state parton energy loss dominates in central Cu+Cu collisions at 62.4 and 200 GeV, while the enhancement at 22.4 GeV is consistent with nuclear modifications in the initial state alone.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 939663
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 15 Vol. 101; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
MODIFICATIONS
PIONS
SPECTRA
TRANSVERSE MOMENTUM