Searching for Ultra-light Bosons and Constraining Black Hole Spin Distributions with Stellar Tidal Disruption Events

TL;DR

This paper explores how stellar tidal disruption events can be used to detect ultra-light bosons and constrain black hole spin distributions, with implications for fundamental physics and astrophysics.

Contribution

It demonstrates that upcoming observations of tidal disruption rates can identify ultra-light bosons and refine black hole spin models, a novel approach in this field.

Findings

Potential to detect ultra-light bosons with masses $10^{-20}$ to $10^{-18}$ eV.

Upcoming surveys can rule out or confirm the existence of these bosons.

Constraints on supermassive black hole spin distributions are achievable.

Abstract

Stars that pass close to the supermassive black holes located in the center of galaxies can be violently disrupted by tidal forces, leading to flares that are observed as bright transient events in sky surveys. The rate for these events to occur depends on the black hole spins, which in turn can be affected by ultra-light bosons due to superradiance. We perform a detailed analysis of these effects and show that searches for stellar tidal disruptions have a significant potential to uncover the existence of ultra-light bosons. In particular, we find that upcoming stellar tidal disruption rate measurements by the Vera Rubin Observatory's Legacy Survey of Space and Time can be used to either discover or rule out bosons with masses ranging from $10^{-20}$ to $10^{-18}$ eV. Our analysis also indicates that these measurements may be used to constrain a variety of supermassive black hole spin distributions and determine if close-to maximal spins are preferred.