Neutron star structure with a new force between quarks

TL;DR

This paper explores how a new force between quarks, arising from gauging baryon number, affects neutron star structure, potentially allowing larger, heavier stars and providing testable predictions at low-energy accelerators.

Contribution

It introduces a novel scenario where a new quark force influences neutron star properties and can be tested with low-energy experiments, unlike other dense matter theories.

Findings

Neutron stars can be larger and heavier due to the new force.

The scenario is testable at low-energy accelerator facilities.

It offers an alternative explanation for massive neutron stars like GW190814 progenitor.

Abstract

The discovery of nondiffuse sources of gravitational waves through compact-object mergers opens new prospects for the study of physics beyond the Standard Model. In this paper, we study the effects of a new force between quarks, suggested by the gauging of baryon number, on pure neutron matter at supranuclear densities. This leads to a stiffening of the equation of state, allowing neutron stars to be both larger and heavier and possibly accommodating the light progenitor of GW190814 as a neutron star. The role of conventional three-body forces in neutron star structure is still poorly understood, though they can act in a similar way, implying that the mass and radius do not in themselves resolve whether new physics is coming into play. However, a crucial feature of the scenario we propose is that the regions of the new physics parameter space that induce observable changes to neutron star structure are testable at low-energy accelerator facilities. This testability distinguishes our scenario from other classes of new phenomena in dense matter.