Pion-Kaon correlations in central Au+Au collisions at square root [sNN] = 130 GeV

Phys Rev Lett. 2003 Dec 31;91(26 Pt 1):262302. doi: 10.1103/PhysRevLett.91.262302. Epub 2003 Dec 31.


Pion-kaon correlation functions are constructed from central Au+Au STAR data taken at sqrt[s(NN)]=130 GeV by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The results suggest that pions and kaons are not emitted at the same average space-time point. Space-momentum correlations, i.e., transverse flow, lead to a space-time emission asymmetry of pions and kaons that is consistent with the data. This result provides new independent evidence that the system created at RHIC undergoes a collective transverse expansion.