Imprints of a critical point on photon emission

TL;DR

This paper explores how a critical point in the QCD phase diagram influences photon emission spectra, suggesting observable signatures in photon data during phase transitions in high-energy nuclear matter.

Contribution

It introduces a model linking critical points in the QCD phase diagram to distinctive features in photon emission spectra during phase transitions.

Findings

Photon spectra exhibit unique signatures near the critical point.

The phase transition influences photon emission rates significantly.

Observable effects depend on the matter’s expansion path crossing the phase boundary.

Abstract

The linear sigma model with linearized fluctuations of all involved fields facilitates the onset of a sequence of first-order phase transitions at a critical point. This phase structure has distinctive imprints on the photon emission rates. We argue that analogously a critical point in the QCD phase diagram manifests itself by peculiarities of the photon spectra, in particular when the dynamical expansion path of matter crosses the phase transition curve in the vicinity of the critical point.