Title：Phase transition in three flavor QCD with background magnetic field

Speaker：Dr. Akio Tomiya (富谷昭夫)， RIKEN-BNL, USA

Time: Sep.24, 15:00PM

Venue：345 Room, Physics Building

Abstract： In this talk, I introduce a phase transition in three flavor QCD under strong magnetic field. We investigate the order of this transition using unimproved and highly improved staggered quarks (HISQ). We discuss the dependences of chiral condensates and susceptibilities and the Polyakov loop on the volume, quark mass and the magnitude of magnetic field. The lattice simulations are performed with several spatial sizes and a fixed temporal size Nt= 4 (Nt=6 for HISQ). The value of the quark masses are chosen such that the system undergoes crossover with zero magnetic field in both formulations. We find that for the standard staggered quarks, the quark chiral condensate undergoes magnetic catalysis in the whole temperature region and the phase transition becomes stronger as the magnetic field increases. The Binder cumulant supports this observation. For the HISQ action, the inverse magnetic catalysis is observed in the critical temperature region and the phase transition tends to become stronger as the magnetic field increases. However, the Binder cumulant does not shows any criticality even for our strongest magnetic field.