Direct photon production in d+Au collisions at √sNN=200 GeV
A. Adare
,
Laurent Aphecetche
(1)
,
X. Camard
(1)
,
Jean-Pierre Cussonneau
(1)
,
H. Delagrange
(1)
,
C. Fink
(1)
,
Marie Germain
(1)
,
A. Hadj Henni
(1)
,
Gines Martinez Garcia
(1)
,
Y. Schutz
(1)
,
S. Gadrat
(2)
,
G. Roche
(2)
,
P. Rosnet
(2)
,
M. P. Comets
(3)
,
B. Espagnon
(3)
,
D. Jouan
(3)
,
Y. Le Bornec
(3)
,
C. Suire
(3)
,
N. Willis
(3)
A. Adare
- Function : Author
Laurent Aphecetche
- Function : Author
- PersonId : 2010
- IdHAL : laurent-aphecetche
- ORCID : 0000-0001-7662-3878
- IdRef : 113847653
Jean-Pierre Cussonneau
- Function : Author
- PersonId : 15492
- IdHAL : jean-pierre-cussonneau
- ORCID : 0000-0001-5061-4973
- IdRef : 122521285
Marie Germain
- Function : Author
- PersonId : 170960
- IdHAL : marie-germain
- ORCID : 0000-0001-7382-1609
- IdRef : 176579958
Gines Martinez Garcia
- Function : Author
- PersonId : 169952
- IdHAL : gines-martinez
- ORCID : 0000-0002-8657-6742
- IdRef : 068952961
Abstract
Direct photons have been measured in √sNN=200 GeV d+Au collisions at midrapidity. A wide pT range is covered by measurements of nearly real virtual photons (1 < pT < 6 GeV/c) and real photons (5 < pT < 16 GeV/c). The invariant yield of the direct photons in d+Au collisions over the scaled p+p cross section is consistent with unity. Theoretical calculations assuming standard cold-nuclear-matter effects describe the data well for the entire pT range. This indicates that the large enhancement of direct photons observed in Au+Au collisions for 1.0 < pT < 2.5 GeV/c is attributable to a source other than the initial-state nuclear effects.