Direct photon production in +Au collisions at GeV
A Adare, SS Adler, S Afanasiev, C Aidala… - Physical Review C …, 2013 - APS
A Adare, SS Adler, S Afanasiev, C Aidala, NN Ajitanand, Y Akiba, H Al-Bataineh, A Al-Jamel…
Physical Review C—Nuclear Physics, 2013•APSDirect photons have been measured in s NN= 200 GeV d+ Au collisions at midrapidity. A
wide p T range is covered by measurements of nearly real virtual photons (1< p T< 6 GeV/c)
and real photons (5< p T< 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 p T
range. This indicates that the large enhancement of direct photons observed in Au+ Au …
wide p T range is covered by measurements of nearly real virtual photons (1< p T< 6 GeV/c)
and real photons (5< p T< 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 p T
range. This indicates that the large enhancement of direct photons observed in Au+ Au …
Direct photons have been measured in GeV collisions at midrapidity. A wide range is covered by measurements of nearly real virtual photons ( GeV/) and real photons ( GeV/). The invariant yield of the direct photons in collisions over the scaled cross section is consistent with unity. Theoretical calculations assuming standard cold-nuclear-matter effects describe the data well for the entire range. This indicates that the large enhancement of direct photons observed in collisions for GeV/ is attributable to a source other than the initial-state nuclear effects.
American Physical Society