Probe the QCD phase diagram with phi-meson production in relativistic nuclear collisions at STAR

We present phi-meson transverse momentum distribution as well as its elliptic flow (v_{2}) measurements in Au + Au collisions at center-of-mass energy per nucleon pair sqrt{s_{NN}} = 7.7, 11.5 and 39 GeV with the data taken from STAR experiment at RHIC in the year 2010. We discuss the energy dependence of phi-meson elliptic flow (v_{2}) and central-to-peripheral nuclear modification factors (R_{CP}). The v_{2} of phi-mesons are compared to those from other hadron species. The implications on partonic-hadronic phase transition are discussed.