https://doi.org/10.1140/epjcd/s2004-03-1702-3
PS06 High Energy Nuclear Physics
Evidence of final-state suppression of high-p
hadrons in Au + Au collisions using d + Au measurements at RHIC
1
Argonne National Laboratory, Argonne, IL 60439-4843, USA
2
Brookhaven National Laboratory, Upton, NY 11973-5000, USA
3
Institute of Nuclear Physics, Kraków, Poland
4
Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA
5
National Central University, Chung-Li, Taiwan
6
University of Illinois at Chicago, Chicago, IL 60607-7059, USA
7
University of Maryland, College Park, MD 20742, USA
8
University of Rochester, Rochester, NY 14627, USA
Received:
1
November
2003
Accepted:
9
February
2004
Published online:
26
February
2004
Transverse momentum spectra of charged hadrons with p
T
< 6 GeV/c have been measured near mid-rapidity (0.2 < η < 1.4) by the PHOBOS experiment at RHIC in Au + Au and d + Au collisions at 
. The spectra for different collision centralities are compared to 
collisions at the same energy. The resulting nuclear modification factor for central Au + Au collisions shows evidence of strong suppression of charged hadrons in the high-p
T
region (>2 GeV/c). In contrast, the d + Au nuclear modification factor exhibits no suppression of the high-p
T
yields. These measurements suggest a large energy loss of the high-p
T
particles in the highly interacting medium created in the central Au + Au collisions. The lack of suppression in d + Au collisions suggests that it is unlikely that initial state effects can explain the suppression in the central Au + Au collisions.
PACS: 25.75.-q
© Società Italiana di Fisica, Springer-Verlag, 2004
