Thermal effects on quark-gluon mixed condensate g from lattice QCD

We present the first study of the thermal effects on the quark-gluon mixed condensate g, which is another chiral order parameter, in the SU(3)c lattice QCD with the Kogut-Susskind fermion at the quenched level. Using the lattices at β=6.0, 6.1, and 6.2 in high statistics, we calculate g as well as in the chiral limit for 0 < or approx. T < or approx. 500 MeV. Except for the sharp decrease of both the condensates around Tc≅280 MeV, the thermal effects are found to be weak below Tc. We also find that the ratio m02≡g/ is almost independent of the temperature even in the very vicinity of Tc. This result indicates nontrivial similarity in the chiral behaviors of the two different condensates