Vector interaction, charge neutrality, and multiple chiral critical-point structures
Vector interaction, charge neutrality, and multiple chiral critical-point structures
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DOI：
10.1103/physrevd.80.014015
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发表时间：
2009-04
影响因子：
5
通讯作者：
Zhao Zhang-;T. Kunihiro
中科院分区：
文献类型：
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作者：
Zhao Zhang-;T. Kunihiro
通过考虑中性色超导电性，研究了排斥矢量相互作用和正电化学势对手征相变的综合影响。在电荷中性约束下，用所谓的Kobayashi-Maskawa-‘t Hooft项求解了双味和二加一味Nambu-Jona-Lasinio模型中的手征凝聚态、双夸克凝聚态和夸克数密度。我们证明了在自洽平均场近似下，Nambu-Jona-Lasinio模型中总是存在多个手性临界点结构，并且手性临界点的数目可以从零变化到四个，这取决于矢量相互作用和双夸克耦合的大小。U夸克和d夸克矢量相互作用所产生的动力学化学势的差异可以有效地减小两种形式的双夸克配对之间的费米球差。因此，矢量相互作用可以显着抑制中性非对称均匀色超导相中与色磁不稳定性相关的不稳定区域。
We investigate the combined effect of the repulsive vector interaction and the positive electric chemical potential on the chiral phase transition by considering neutral color superconductivity. The chiral condensate, diquark condensate, and quark number densities are solved in both two-flavor and two-plus-one-flavor Nambu-Jona-Lasinio models with the so called Kobayashi-Maskawa-'t Hooft term under the charge-neutrality constraint. We demonstrate that multiple chiral critical-point structures always exist in the Nambu-Jona-Lasinio model within the self-consistent mean-field approximation, and that the number of chiral critical points can vary from zero to four, which is dependent on the magnitudes of vector interaction and the diquark coupling. The difference between the dynamical chemical potentials induced by vector interaction for u and d quarks can effectively reduce the Fermi sphere disparity between the two flavors of diquark pairing. Thus the vector interaction works to significantly suppress the unstable region associated with chromomagnetic instability in the phase of neutral asymmetric homogeneous color superconductivity.