Exploring the robustness of stellar cooling constraints on light particles

TL;DR

This paper examines how thermodynamic principles limit the ability of new physics models to evade stellar cooling constraints and proposes a minimal extension that reopens parameter space, emphasizing laboratory experiments' importance.

Contribution

It introduces a minimal model extension that allows new particles to bypass stellar constraints, highlighting the role of laboratory experiments in new physics searches.

Findings

A thermodynamic argument restricts evasion of stellar constraints.

A minimal model extension can bypass these constraints.

Reopened parameter space can explain signals like EDGES and Xenon1T.

Abstract

Stellar cooling arguments place strict restrictions on a wide variety of models of new physics. In this paper, we argue that mechanisms to evade these constraints are restricted by thermodynamic arguments, then present a minimal model extension that allows new particles to evade all stellar constraints. In doing this, we demonstrate that interesting parameter space can be reopened, using the EDGES signal and Xenon1T excess as examples. This mechanism highlights the importance of laboratory experiments in a well-controlled environment to search for new physics, complementary to astrophysical searches.