Equation of state in (2+1)-flavor QCD at physical point with improved Wilson fermion action using gradient flow

¹ Center for Integrated Research in Fundamental Science and Engineering (CiRfSE), University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
² Department of Physics, Niigata University, Niigata, Niigata 950-2181, Japan
³ Track Maintenance of Shinkansen, Rail Maintenance 1st Department, East Japan Railway Company Niigata Branch, Niigata, Niigata 950-0086, Japan
⁴ Department of Physics, Osaka University, Osaka, Osaka 560-0043, Japan
⁵ J-PARC Branch, KEK Theory Center, Institute of Particle and Nuclear Studies, KEK, 203-1, Shirakata, Tokai, Ibaraki 319-1106, Japan
⁶ Department of Physics, Kyushu University, 744 Motooka, Fukuoka, Fukuoka 819-0395, Japan
⁷ Center for Computational Sciences (CCS), University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
⁸ Graduate School of Education, Hiroshima University, Higashihiroshima, Hiroshima 739-8524, Japan

^* Speaker, e-mail: kanaya@ccs.tsukuba.ac.jp, present address: Tomonaga Center for the History of the Universe, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan

Published online: 26 March 2018

Abstract

We study the energy-momentum tensor and the equation of state as well as the chiral condensate in (2+1)-flavor QCD at the physical point applying the method of Makino and Suzuki based on the gradient flow. We adopt a nonperturbatively O(a)- improved Wilson quark action and the renormalization group-improved Iwasaki gauge action. At Lattice 2016, we have presented our preliminary results of our study in (2+1)- flavor QCD at a heavy u; d quark mass point. We now extend the study to the physical point and perform finite-temperature simulations in the range T ≃ 155.544 MeV (N_t = 4-14 including odd N_t’s) at a ≃ 0:09 fm. We show our final results of the heavy QCD study and present some preliminary results obtained at the physical point so far.