# Phase Diagram, Scalar-Pseudoscalar Meson Behavior and Restoration of Symmetries in (2+1) Polyakov-Nambu-Jona-Lasinio Model

## TL;DR

This paper investigates the phase diagram and mesonic behavior in a (2+1) Polyakov-Nambu-Jona-Lasinio model, highlighting the chiral critical end point and meson mass changes as indicators of symmetry restoration.

## Contribution

It provides a detailed analysis of the phase diagram and mesonic observables, emphasizing the role of the CEP and meson mass variations in symmetry restoration.

## Key findings

- Kaon masses change abruptly near the CEP
- Chiral and deconfinement transitions are characterized
- Isentropic trajectories are mapped in the phase diagram

## Abstract

We explore the phase diagram and the modification of mesonic observables in a hot and dense medium using the (2+1) Polyakov-Nambu-Jona-Lasinio model. We present the phase diagram in the ($T,\,\mu_B$)-plane, with its isentropic trajectories, paying special attention to the chiral critical end point (CEP). Chiral and deconfinement transitions are examined. The modifications of mesonic observables in the medium are explored as a tool to analyze the effective restoration of chiral symmetry for different regions of the phase diagram. It is shown that the meson masses, namely that of the kaons, change abruptly near the CEP, which can be relevant for its experimental search.