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Thermal effects on quark-gluon mixed condensate g<\bar{q} σG q> from lattice QCD

Takumi Doi·Noriyoshi Ishii·Makoto Oka·Hideo Suganuma
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Abstract

We present the first study of the thermal effects on the quark-gluon mixed condensate g<\bar{q} σG q>, which is another chiral order parameter, in SU(3)c lattice QCD with the Kogut-Susskind fermion at the quenched level. Using the lattices at β=6.0, 6.1, 6.2 in high statistics, we calculate the mixed condensate as well as the quark condensate in the chiral limit for the temperature 0MeV <= T <= 500MeV. Except for the sharp decrease of both the condensates around T_c \simeq 280MeV, the thermal effects are found to be weak below T_c. We also find that the ratio m_0^2 = g<\bar{q} σG q>/ <\bar{q}q> is almost independent of the temperature even in the very vicinity of T_c. This result indicates nontrivial similarity in the chiral behaviors of the two different condensates.

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Takumi Doi, Noriyoshi Ishii, Makoto Oka, Hideo Suganuma. 2004-06-18. Thermal effects on quark-gluon mixed condensate g<\bar{q} σG q> from lattice QCD. https://doi.org/10.1103/physrevd.70.034510

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