Abstract
The short-lived resonance provides an efficient tool to probe properties of the hot and dense medium produced in relativistic heavy-ion collisions. We report measurements of in Au+Au and collisions reconstructed via its hadronic decay channels and using the STAR detector at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The mass has been studied as a function of in minimum bias and central Au+Au collisions. The spectra for minimum bias interactions and for Au+Au collisions in different centralities are presented. The yield ratios for all centralities in Au+Au collisions are found to be significantly lower than the ratio in minimum bias collisions, indicating the importance of hadronic interactions between chemical and kinetic freeze-outs. A significant nonzero elliptic flow () is observed in Au+Au collisions and is compared to the and Λ . The nuclear modification factor of at intermediate is similar to that of but different from Λ. This establishes a baryon-meson effect over a mass effect in the particle production at intermediate ().
9 More- Received 9 December 2004
DOI:https://doi.org/10.1103/PhysRevC.71.064902
©2005 American Physical Society