Tidal Love Numbers of Novel and Admixed Celestial Objects

TL;DR

This paper explores how new particles inside celestial objects like neutron stars and boson stars affect their properties, especially the tidal love number, which can be measured by upcoming gravitational wave detectors.

Contribution

It introduces a generic framework to solve TOV equations for objects with multiple fluids, including new physics effects, and makes this code publicly available.

Findings

New particles can create extended atmospheres in celestial objects.

Tidal love numbers are sensitive to the presence of new particles and interactions.

Framework enables modeling of novel and admixed celestial objects with arbitrary new physics.

Abstract

A sub-fraction of dark matter or new particles trapped inside celestial objects can significantly alter their macroscopic properties. We investigate the new physics imprint on celestial objects by using a generic framework to solve the Tolman-Oppenheimer-Volkoff (TOV) equations for up to two fluids. We test the impact of populations of new particles on celestial objects, including the sensitivity to self-interaction sizes, new particle mass, and net population mass. Applying our setup to neutron stars and boson stars, we find rich phenomenology for a range of these parameters, including the creation of extended atmospheres. These atmospheres are detectable by their impact on the tidal love number, which can be measured at upcoming gravitational wave experiments such as Advanced LIGO, the Einstein Telescope, and LISA. We release our calculation framework as a publicly available code, allowing the TOV equations to be generically solved for arbitrary new physics models in novel and admixed celestial objects.