Abstract
The STAR Collaboration at the Relativistic Heavy Ion Collider presents a systematic study of high-transverse-momentum charged-di-hadron correlations at small azimuthal pair separation in and central collisions at GeV. Significant correlated yield for pairs with large longitudinal separation is observed in central collisions, in contrast to collisions. The associated yield distribution in can be decomposed into a narrow jet-like peak at small angular separation which has a similar shape to that found in collisions, and a component that is narrow in and depends only weakly on , the “ridge.” Using two systematically independent determinations of the background normalization and shape, finite ridge yield is found to persist for trigger , indicating that it is correlated with jet production. The transverse-momentum spectrum of hadrons comprising the ridge is found to be similar to that of bulk particle production in the measured range ().
- Received 1 September 2009
DOI:https://doi.org/10.1103/PhysRevC.80.064912
©2009 American Physical Society