Impact of resonance decays on critical point signals in net-proton fluctuations

TL;DR

This paper investigates how resonance decays influence signals of the QCD critical point in net-proton fluctuation measurements, finding that while they diminish these signals, critical effects can still be observed under realistic conditions.

Contribution

It provides a detailed analysis of resonance decay effects on critical fluctuation signals, demonstrating their impact and conditions under which critical signatures remain detectable.

Findings

Resonance decays reduce critical fluctuation signals.

Critical effects in net-proton cumulants can survive resonance effects.

Higher-order cumulants experience slightly stronger suppression.

Abstract

The non-monotonic beam energy dependence of the higher cumulants of net-proton fluctuations is a widely studied signature of the conjectured presence of a critical point in the QCD phase diagram. In this work we study the effect of resonance decays on critical fluctuations. We show that resonance effects reduce the signatures of critical fluctuations, but that for reasonable parameter choices critical effects in the net-proton cumulants survive. The relative role of resonance decays has a weak dependence on the order of the cumulants studied with a slightly stronger suppression of critical effects for higher-order cumulants.