Identified haron spectra at large transerve momentum in p+p and d+Au collisions at {radical}{ovr s}{sub NN} = 200 GeV.

Journal Article · Sun Jan 01 04:00:00 EST 2006 · Phys. Rev. B

DOI:https://doi.org/10.1016/j.physletb.2006.04.032· OSTI ID:966034

Cadman, R V; Krueger, K; McClain, C J; Spinka, H M; Underwood, D G; Adams, J; Aggarwal, M M; Ahammed, Z; Amonett, J; Anderson, M; BNL,

We present the transverse momentum (p{sub T}) spectra for identified charged pions, protons and anti-protons from p+p and d+Au collisions at {radical}s{sub NN} = 200 GeV. The spectra are measured around midrapidity (|y| < 0.5) over the range of 0.3 < p{sub T} < 10 GeV/c with particle identification from the ionization energy loss and its relativistic rise in the time projection chamber and time-of-flight in STAR. The charged pion and proton + anti-proton spectra at high p{sub T} in p+p and d+Au collisions are in good agreement with a phenomenological model (EPOS) and with next-to-leading order perturbative quantum chromodynamic (NLO pQCD) calculations with a specific fragmentation scheme and factorization scale. We found that all proton, anti-proton and charged pion spectra in p+p collisions follow x{sub T}-scaling for the momentum range where particle production is dominated by hard processes (p{sub T} {ge} 2 GeV/c). The nuclear modification factor around midrapidity is found to be greater than unity for charged pions and to be even larger for protons at 2 < p{sub T} < 5 GeV/c.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC; NSF; Swiss NSF
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 966034
• Report Number(s): ANL-HEP-PR-09-64
• Journal Information: Phys. Rev. B, Journal Name: Phys. Rev. B Journal Issue: 2006 Vol. 637; ISSN 1098-0121
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
FACTORIZATION
FRAGMENTATION
IONIZATION
MODIFICATIONS
PARTICLE IDENTIFICATION
PARTICLE PRODUCTION
PIONS
PROTONS
QUANTUM CHROMODYNAMICS
SPECTRA
TIME PROJECTION CHAMBERS
TRANSVERSE MOMENTUM