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arXiv · hep-ph/0312005

Four-fermion Interaction Model in a Constant Magnetic Field at Finite Temperature and Chemical Potential

Tomohiro Inagaki·Daiji Kimura·Tsukasa Murata
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Abstract

We investigate an influence of an external magnetic field on chiral symmetry breaking in a four-fermion interaction model at finite temperature and chemical potential. By using the Fock-Schwinger proper-time method, we calculate the effective potential for the four-fermion interaction model at the leading order of the $1/N_c$ expansion. A phase structure of the chiral symmetry breaking is shown on $T$-$μ$, $H$-$T$ and $μ$-$H$ planes. The external magnetic field modifies the phase structure. It is found that a new phase appears for a large chemical potential.

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Tomohiro Inagaki, Daiji Kimura, Tsukasa Murata. 2004-03-15. Four-fermion Interaction Model in a Constant Magnetic Field at Finite Temperature and Chemical Potential. https://doi.org/10.1143/ptp.111.371

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