Azimuthal di-hadron correlations in d + Au and Au+Au collisions at √sNN = 200 GeV measured at the STAR detector

Yields, correlation shapes, and mean transverse momenta p{sub T} of charged particles associated with intermediate- to high-p{sub T} trigger particles (2.5 or approx. 2.5 GeV/c, narrow correlation peaks are seen in d+ Au and Au + Au, indicating that the main production mechanism is jet fragmentation. At lower associated particle p{sub T}<2 GeV/c, a large enhancement of the near- ({Delta}{phi}{approx}0) and away-side ({Delta}{phi}{approx}{pi}) associated yields is found, together with a strong broadening of the away-side azimuthal distributions in Au + Au collisions compared to d+ Au measurements, suggesting that other particle production mechanisms play a role. This is further supported by the observed significant softening of the away-side associated particle yield distribution at {Delta}{phi}{approx}{pi} in central Au + Au collisions.