Finite volume effects in the extended linear sigma model via low momentum cutoff

TL;DR

This paper investigates how finite volume effects influence the thermodynamics and phase transition properties of strongly interacting matter using a low momentum cutoff in an extended linear sigma model.

Contribution

It introduces a method to incorporate finite volume effects into an effective model via a low momentum cutoff, revealing significant impacts on thermodynamics and phase transition features.

Findings

Finite volume alters the thermodynamic quantities.

The critical endpoint location shifts due to finite size effects.

Finite volume effects are significant in small systems like heavy-ion collisions.

Abstract

Contrary to field theoretical calculations in the thermodynamic limit where the volume is assumed to be infinitely large, the heavy-ion collisions always carry the effects of finite size. A sufficiently small system size is expected to affect the thermodynamic quantities and the phase diagram of the strongly interacting matter. To study these effects one can take into account the finite spatial extent of the system within the framework of an effective model too, via the restriction of the momentum integrals using discretization or in a simplified case using a low momentum cutoff. We investigated the effects of the finite volume in a vector meson extended Polyakov quark-meson model and found a remarkable change in the thermodynamics and the phase transition, especially in the location of the critical endpoint.