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arXiv · 1803.00032

Mesons and diquarks in a color superconducting regime

Abstract

The behavior of the mesons and diquarks is studied at finite temperatures, chemical potentials and densities, notably when the color superconductivity is taken into account. The Nambu and Jona-Lasinio model complemented by a Polyakov loop (PNJL description) has been adapted in order to model these composite particles in this regime. This paper focuses on the scalar and pseudo-scalar mesons and diquarks, in a three-flavor and three-color description, with the isospin symmetry and at null strangeness. A finality of this work is to underline the modifications carried out by the color superconducting regime on the used equations and on the obtained results. It has been observed that the two-flavor color-superconducting (2SC) phase affects the masses of the mesons and diquarks in a non-negligible way. This observation is particularly true at high densities and low temperatures for the pions, $η$ and the diquarks [ud] whose color is rg. This reveals that the inclusion of the color superconductivity is relevant to describe the mesons and diquarks near the first order chiral phase transition.

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BibTeXRIS

Eric Blanquier. 2018-02-28. Mesons and diquarks in a color superconducting regime. https://doi.org/10.1142/s0217751x2150264x

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