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The Quark-Gluon Mixed Condensate g<\bar{q} sigma G q> in SU(3)c Quenched Lattice QCD

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

Using the SU(3)c lattice QCD with the Kogut-Susskind fermion at the quenched level, we study the quark-gluon mixed condensate g<\bar{q} sigma G q>, which is another chiral order parameter. For each current quark mass of m_q=21, 36, 52 MeV, we generate 100 gauge configurations in the 16^4 lattice with β= 6.0, and perform the measurement of the mixed condensate at 16 points in each gauge configuration. Using the 1600 data for each m_q, we find the ratio between the mixed condensate and the quark condensate, m_0^2 = g<\bar{q} sigma G q>/ <\bar{q}q> \simeq 2.5 GeV^2 at the lattice scale in the chiral limit. The large value of the mixed condensate suggests its importance in the operator product expansion in QCD.

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Takumi Doi, Noriyoshi Ishii, Makoto Oka, Hideo Suganuma. 2003-01-24. The Quark-Gluon Mixed Condensate g<\bar{q} sigma G q> in SU(3)c Quenched Lattice QCD. https://doi.org/10.1103/physrevd.67.054504

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