We present the recent results of strangeness production at the mid-rapidity in Au + Au collisions at RHIC, from √sNN = 7.7 to 200 GeV. Elliptic asymmetry v2of multi-strange baryon Ωand φmesons are similar to that of pions and protons in the intermediate pT range (2-5 GeV/c) in √sNN = 200 GeV Au + Au collisions, indicating that the major part of collective ow has been built up at partonic stage. The breaking of mass ordering between φmesons and protons in the low pT range (<1 GeV/c) is consistent with a picture that φmesons are less sensitive to later hadronic i...
