Abstract
The short-lived K(892)* resonance provides an efficient tool to probe properties of the hot and dense medium produced in relativistic heavy-ion collisions. We report measurements of K* in sNN=200GeV Au+Au and p+p collisions reconstructed via its hadronic decay channels K(892) *0→Kπ and K(892)*±→KS0π± using the STAR detector at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The K*0 mass has been studied as a function of pT in minimum bias p+p and central Au+Au collisions. The K*pT spectra for minimum bias p+p interactions and for Au+Au collisions in different centralities are presented. The K*/K yield ratios for all centralities in Au+Au collisions are found to be significantly lower than the ratio in minimum bias p+p collisions, indicating the importance of hadronic interactions between chemical and kinetic freeze-outs. A significant nonzero K*0 elliptic flow (v2) is observed in Au+Au collisions and is compared to the KS0 and Λ v2. The nuclear modification factor of K* at intermediate pT is similar to that of KS0 but different from Λ. This establishes a baryon-meson effect over a mass effect in the particle production at intermediate pT (2