Jet-like correlations with direct-photon and neutral-pion triggers at s_NN=200 GeV

Azimuthal correlations of charged hadrons with direct-photon (γ_dir) and neutral-pion (π⁰) trigger particles are analyzed in central Au+Au and minimum-bias p+p collisions at s_NN=200 GeV in the STAR experiment. The charged-hadron per-trigger yields at mid-rapidity from central Au+Au collisions are compared with p+p collisions to quantify the suppression in Au+Au collisions. The suppression of the away-side associated-particle yields per γ_dir trigger is independent of the transverse momentum of the trigger particle (p_T^trig), whereas the suppression is smaller at low transverse momentum of the associated charged hadrons (p_T^assoc). Within uncertainty, similar levels of suppression are observed for γ_dir and π⁰ triggers as a function of z_T (≡p_T^assoc/p_T^trig). The results are compared with energy-loss-inspired theoretical model predictions. Our studies support previous conclusions that the lost energy reappears predominantly at low transverse momentum, regardless of the trigger energy.