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Chemical potential response of pseudoscalar meson masses in the Nambu--Jona-Lasinio model

O. Miyamura·S. Choe
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Abstract

Using the Nambu--Jona-Lasinio (NJL) model we study chemical potential response of the pion and kaon masses as a function of temperature and chemical potential, i.e., dm/dμ(T, μ). First, we obtain the responses assuming the vector-axial vector coupling is zero (g_V=0). Then, we include a non-zero g_V and study the effects of g_V on the responses. We find that the behavior of dm/dμfor the pion is quite different from that for the kaon. It means that dm/dμis much dependent on the mass difference between the two quarks, i.e., the u and s quarks (or even between the u and d quarks). Our results may give a clue to future studies of dm/dμon the lattice.

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O. Miyamura, S. Choe. 2001-10-31. Chemical potential response of pseudoscalar meson masses in the Nambu--Jona-Lasinio model. https://arxiv.org/abs/hep-lat/0110089

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