Strange-quark collectivity of the φ-meson at RHIC

Based on A Multi-Phase Transport (AMPT) model, the elliptic flow v2 of φ-mesons which is reconstructed from K +K- at the Relativistic Heavy-Ion Collider (RHIC) energy has been studied. The results show that the reconstructed v2 of the φ-meson can keep the earlier information before φ decays and it seems to obey the number of constituent-quark scaling as other mesons and baryons. This result indicates that the φ v2 mostly reflects the parton level collectivity developed during the early stage of the collisions and the strange and light up/down quarks have similar collectivity properties before the hadronization. (orig.)