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Effect of $U_A(1)$ Breaking on Chiral Phase Structure and Pion Superfluidity at Finite Isospin Chemical Potential

Lianyi He·Meng Jin·Pengfei Zhuang
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Abstract

We investigate the isospin chemical potential effect in the frame of SU(2) Nambu-Jona-Lasinio model. When the isospin chemical potential is less than the vacuum pion mass, the phase structure with two chiral phase transition lines does not happen due to $U_A(1)$ breaking of QCD. When the isospin chemical potential is larger than the vacuum pion mass, the ground state of the system is a Bose-Einstein condensate of charged pions.

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Lianyi He, Meng Jin, Pengfei Zhuang. 2006-02-19. Effect of $U_A(1)$ Breaking on Chiral Phase Structure and Pion Superfluidity at Finite Isospin Chemical Potential. https://doi.org/10.1142/s0217732307023237

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