Photon Signals from Quarkyonic Matter

TL;DR

This paper investigates photon emission spectra from quarkyonic matter, revealing distinctive features in transverse momentum distribution and elliptic flow that could serve as signatures of this phase in high-energy nuclear collisions.

Contribution

It provides the first detailed calculation of photon signals from quarkyonic matter, highlighting unique spectral and flow characteristics compared to quark-gluon plasma and hadron gas.

Findings

Photon spectrum from quarkyonic matter is steeper than in QGP or hadron gas.

Elliptic flow coefficient fluctuates randomly, indicating a unique quarkyonic signature.

Transverse momentum distribution fits an exponential form, distinct from other phases.

Abstract

We calculate the Bremsstrahlung photon spectrum emitted from dynamically evolving quarkyonic matter, and compare this spectrum with that of a high chemical potential quark-gluon plasma as well as to a hadron gas. We find that the transverse momentum distribution and the harmonic coefficient is markedly different in the three cases. The transverse momentum distribution of quarkyonic matter can be fit with an exponential, but is markedly steeper than the distribution expected for the quark-gluon plasma or a hadron gas, even at the lower temperatures expected in the critical point region. The quarkyonic elliptic flow coefficient fluctuates randomly from event to event, and within the same event at different transverse momenta. The latter effect, which can be explained by the shape of quark wavefunctions within quarkyonic matter, might be considered as a quarkyonic matter signature, provided initial temperature is low enough that the quarkyonic regime dominates over deconfinement effects, and the reaction-plane flow can be separated from the fluctuating component.