Onset of {pi}{sup 0} Suppression Studied in Cu+Cu Collisions at {radical}(s{sub NN})=22.4, 62.4, and 200 GeV

Journal Article · Fri Oct 17 04:00:00 EDT 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.101.162301· OSTI ID:21179812

Adare, A; Bickley, A A; Ellinghaus, F; Glenn, A; Kinney, E; Kiriluk, K; Nagle, J L; Seele, J; Wysocki, M ^[1]; Afanasiev, S; Isupov, A; Litvinenko, A; Malakhov, A; Peresedov, V; Rukoyatkin, P; Zolin, L ^[2]; Aidala, C ^[3]; Ajitanand, N N; Alexander, J; Chung, P ^[4]

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1. University of Colorado, Boulder, Colorado 80309 (United States)
2. Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation)
3. Columbia University, New York, New York 10027, USA and Nevis Laboratories, Irvington, New York 10533 (United States)
4. Chemistry Department, Stony Brook University, SUNY, Stony Brook, New York 11794-3400 (United States)

Neutral pion transverse momentum (p{sub T}) spectra at midrapidity (|y| < or approx. 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}(> or approx. 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.

• OSTI ID: 21179812
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 16 Vol. 101; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
COLLIDING BEAMS
COPPER 63 BEAMS
COPPER 63 REACTIONS
COPPER 63 TARGET
ENERGY LOSSES
GEV RANGE 10-100
GEV RANGE 100-1000
INELASTIC SCATTERING
PIONS NEUTRAL
PROTON-PROTON INTERACTIONS
TRANSVERSE MOMENTUM