Finite volume effects on chiral phase transition and pseudoscalar mesons properties from the Polyakov-Nambu-Jona-Lasinio model

Abstract

Within the framework of Polyakov-Nambu-Jona-Lasinio model and by means of Multiple Reflection Expansion, we study the finite volume effects on chiral phase transition, especially its influence on the location of the possible critical end point (CEP) and masses of mesons. Our result shows that as the radius of spherical volume decreases, the location of CEP shifts toward smaller temperature while changes little in chemical potential. As for the finite volume effects on the masses of mesons, the masses of π and K increase with decreasing volume, while for σ, η and η ′ the situation is the opposite. Especially, the masses of chiral parters π and σ get closer as the volume decreases, indicating that the dynamical chiral symmetry breaking effect reduces with decreasing volume.

Properties of neutral mesons in a hot and magnetized quark matter: size-dependent effects

“…In particular, the σ mass reaches a minimum at the critical point of chiral phase transition T ξ c , and then rises in the unbroken restored phase. This is in qualitative agreement with previous findings, as those from [19,[23][24][25][26]52]. The finite size effects appear as follows: at sufficiently small values of L the masses are also modified in a different way.…”

“…With regard to other studies (see for example Refs. [19,[23][24][25][26]52]), which employed different treatments and methods to account for the finite volume or thermomagnetic effects, our aim is to discuss the combination/competition of them in a unified way.…”

“…In this sense, the pseudo-critical temperature where the π 0 and σ meson masses start to degenerate also reduces with the decreasing of L. It is worthy remarking that an analogous effect is reported in Refs. [42,52] by using distinct treatments. Now we focus on the evaluation of combined finitesize and thermomagnetic effects.…”

Chiral transition and the chiral charge density of the hot and dense QCD matter.

“…Meanwhile, the finite size effect could be relevant for the CME experiments since the CME is typically investigated with peripheral collisions. Note that the finite size effect on QCD phase diagram on T − µ plane had been studied with various methods [45][46][47][48][49][50][51], but its influence on the chirally imbalanced medium was seldom studied. For a first investigation, we will consider the system in a cubic box of edge length L.…”

Nonextensive effects on QCD chiral phase diagram and baryon-number fluctuations within Polyakov-Nambu-Jona-Lasinio model

“…Since the discovery of quark-gluon plasma (QGP) at the Relativistic Heavy-Ion Collider (RHIC) and Large Hadron Collider (LHC), the determination of QCD phase diagram at high quark chemical potential, especially the search for the location of critical end point (CEP), has been the focus of experiments, such as the BES-II program at RHIC and the CBM experiment at FAIR. Theoretically, due to the "sign problem" encountered by lattice QCD, people use various effective models to study the QCD phase diagram, such as chiral perturbation theory [1], finite energy sum rules [2], Dyson-Schwinger Equations (DSEs) [3][4][5], Nambu-Jona-Lasinio (NJL) model and Polyakov-Nambu-Jona-Lasinio (PNJL) model [6][7][8][9][10].…”