Identified hadron transverse momentum spectra in Au+Au collisions at {radical}(s{sub NN})=62.4 GeV

Journal Article · Thu Feb 15 00:00:00 EST 2007 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.75.024910· OSTI ID:20991036

Back, B B ^[1]; Baker, M D; Barton, D S; Carroll, A; Chai, Z; George, N; Hauer, M; Holzman, B; Pak, R; Seals, H; Sedykh, I; Stankiewicz, M A; Steinberg, P; Sukhanov, A ^[2]; Ballintijn, M; Busza, W; Decowski, M P; Gulbrandsen, K; Henderson, C; Kane, J L ^[3]

---

1. Argonne National Laboratory, Argonne, Illinois 60439-4843 (United States)
2. Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)
3. Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States)

Transverse momentum spectra of pions, kaons, protons, and antiprotons from Au+Au collisions at {radical}(s{sub NN}) = 62.4 GeV have been measured by the PHOBOS experiment at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The identification of particles relies on three different methods: low momentum particles stopping in the first detector layers; the specific energy loss (dE/dx) in the silicon spectrometer, and time-of-flight measurement. These methods cover the transverse momentum ranges 0.03-0.2, 0.2-1.0, and 0.5-3.0 GeV/c, respectively. Baryons are found to have substantially harder transverse momentum spectra than mesons. The p{sub T} region in which the proton to pion ratio reaches unity in central Au+Au collisions at {radical}(s{sub NN}) = 62.4 GeV fits into a smooth trend as a function of collision energy. At low transverse mass, the spectra of various species exhibit a significant deviation from transverse mass scaling. The observed particle yields at very low p{sub T} are comparable to extrapolations from higher p{sub T} for kaons, protons and antiprotons. By comparing our results to Au+Au collisions at {radical}(s{sub NN}) = 200 GeV, we conclude that the net proton yield at midrapidity is proportional to the number of participant nucleons in the collision.

• OSTI ID: 20991036
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 75, Issue 2; Other Information: DOI: 10.1103/PhysRevC.75.024910; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTIPROTONS
BNL
BROOKHAVEN RHIC
COLLISIONS
ENERGY LOSSES
EXTRAPOLATION
GEV RANGE
KAONS
MASS
PARTICLES
PIONS
SILICON
SPECTRA
TRANSVERSE MOMENTUM