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arXiv · 1109.1096

QCD Chiral restoration at finite $T$ under the Magnetic field: Studies based on the instanton vacuum model

Chung Wen Kao·Seung-il Nam
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Abstract

We investigate the chiral restoration at finite temperature $(T)$ under the strong external magnetic field $\vec{B}=B_{0}\hat{z}$ of the SU(2) light-flavor QCD matter. We employ the instanton-liquid QCD vacuum configuration accompanied with the linear Schwinger method for inducing the magnetic field. The Harrington-Shepard caloron solution is used to modify the instanton parameters, i.e. the average instanton size $(\bar{\rho})$ and inter-instanton distance $(\bar{R})$, as functions of $T$. In addition, we include the meson-loop corrections (MLC) as the large-$N_{c}$ corrections because they are critical for reproducing the universal chiral restoration pattern. We present the numerical results for the constituent-quark mass as well as chiral condensate which signal the spontaneous breakdown of chiral-symmetry (SB$\chi$S), as functions of $T$ and $B$. Besides we find that the changes for the $F_\pi$ and $m_\pi$ due to the magnetic field is relatively small, in comparison to those caused by the finite $T$ effect.

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Chung Wen Kao, Seung-il Nam. 2011-09-06. QCD Chiral restoration at finite $T$ under the Magnetic field: Studies based on the instanton vacuum model. https://doi.org/10.1007/s00601-012-0352-z

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