Centrality dependence of charged hadron transverse momentum spectra in Au+Au collisions from sqrt[s(NN)]=62.4 to 200 GeV.
We have measured transverse momentum distributions of charged hadrons produced in Au+Au collisions at sqrt[s(NN)]=62.4 GeV. The spectra are presented for transverse momenta 0.25<p(T)<4.5 GeV/c, in a pseudorapidity range of 0.2<eta<1.4. The nuclear modification factor R(AA) is calculated relative to p+p data at the same collision energy as a function of collision centrality. For 2<p(T)<4.5 GeV/c, R(AA) is found to be significantly larger than in Au+Au collisions at sqrt[s(NN)]= 130 and 200 GeV. In contrast to the large change in R(AA), we observe a very similar centrality evolution of the p(T) spectra at sqrt[s(NN)]=62.4 and 200 GeV. The dynamical origin of this surprising factorization of energy and centrality dependence of particle production in heavy-ion collisions remains to be understood.
Back
B B
BB
Argonne National Laboratory, Argonne, IL 60439-4843, USA.
Baker
M D
MD
Ballintijn
M
M
Barton
D S
DS
Betts
R R
RR
Bickley
A A
AA
Bindel
R
R
Busza
W
W
Carroll
A
A
Chai
Z
Z
Decowski
M P
MP
García
E
E
Gburek
T
T
George
N
N
Gulbrandsen
K
K
Halliwell
C
C
Hamblen
J
J
Hauer
M
M
Henderson
C
C
Hofman
D J
DJ
Hollis
R S
RS
Hołyński
R
R
Holzman
B
B
Iordanova
A
A
Johnson
E
E
Kane
J L
JL
Khan
N
N
Kulinich
P
P
Kuo
C M
CM
Lin
W T
WT
Manly
S
S
Mignerey
A C
AC
Nouicer
R
R
Olszewski
A
A
Pak
R
R
Reed
C
C
Roland
C
C
Roland
G
G
Sagerer
J
J
Seals
H
H
Sedykh
I
I
Smith
C E
CE
Stankiewicz
M A
MA
Steinberg
P
P
Stephans
G S F
GS
Sukhanov
A
A
Tonjes
M B
MB
Trzupek
A
A
Vale
C
C
van Nieuwenhuizen
G J
GJ
Vaurynovich
S S
SS
Verdier
R
R
Veres
G I
GI
Wenger
E
E
Wolfs
F L H
FL
Wosiek
B
B
Woźniak
K
K
Wysłouch
B
B