Physical Review C
We report the observation at the Relativistic Heavy Ion Collider of suppression of back-to-back correlations in the direct photon+jet channel in Au+Au relative to p+p collisions. Two-particle correlations of direct photon triggers with associated hadrons are obtained by statistical subtraction of the decay photon-hadron (γ-h) background. The initial momentum of the away-side parton is tightly constrained, because the parton-photon pair exactly balance in momentum at leading order in perturbative quantum chromodynamics, making such correlations a powerful probe of the in-medium parton energy loss. The away-side nuclear suppression factor, IAA, in central Au+Au collisions, is 0.32±0.12stat±0.09syst for hadrons of 3
Adare, Andrew Marshall; Baksay, Gyöngyi; Baksay, László A.; Dehmelt, Klaus; Hohlmann, Marcus; and Rembeczki, S., "Photon-Hadron Jet Correlations In p+p And Au+Au Collisions At √sNN = 200 GeV" (2009). Aerospace, Physics, and Space Science Faculty Publications. 389.