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The quark-gluon Mixed Condensate calculated via Field Correlators

A. Di Giacomo·Yu. A. Simonov
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Abstract

The quark-gluon mixed condensate $g<\bar q σ_{μν} F_{μν} q>$ is calculated in the Gaussian approximation of the Field Correlator Method. In the large N_c limit and for zero mass quarks one obtains a simple result, $m^2_0 \equiv \frac{g<\bar q σ_{μν} F_{μν} q>}{<\bar q q>} = \frac{16σ}π$, where $σ$ is the string tension. For a standard value $σ=0.18 GeV^2$ one obtains $m^2_0=1 GeV^2$ in good agreement with the QCD sum rules estimate $m^2_0 = (0.8\pm 0.2) GeV^2$ and the latest lattice result $m^2_0 \cong 1 GeV^2$.

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A. Di Giacomo, Yu. A. Simonov. 2004-06-01. The quark-gluon Mixed Condensate calculated via Field Correlators. https://doi.org/10.1016/j.physletb.2004.06.036

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