Locating critical point of QCD phase transition basing on finite-size scaling

It is argued that in relativistic heavy ion collisions, due to limited size of the formed matter, the reliable criterion of critical point is finite-size scaling, rather than non-monotonous behavior of observable. How to locate critical point by finite-size scaling is proposed. The data of $\pt$ correlation from RHIC/STAR are analyzed. Critical points are likely observed around $\sqrt s =62$ and 200 GeV. They could be, respectively, the transition of deconfinement and chiral symmetry restoration predicted by lattice-QCD. Further confirmation with other observable and energies is suggested.