Multi-Messenger Constraint on the Hubble Constant $H_0$ with Tidal Disruption Events

TL;DR

This paper proposes a novel method to measure the Hubble constant using tidal disruption events by combining electromagnetic and gravitational wave data, potentially providing a model-independent cosmological constraint.

Contribution

It introduces a new approach to constrain $H_0$ by integrating TDE parameters from EM observations into GW waveform analysis, addressing the distance-inclination degeneracy.

Findings

Method to incorporate TDE parameters into GW analysis.

Potential for independent $H_0$ measurement from individual TDEs.

Use of BH spin to improve distance estimates.

Abstract

Tidal disruption events (TDEs), apart from producing luminous electromagnetic (EM) flares, can generate potentially detectable gravitational wave (GW) burst signals by future space-borne GW detectors. In this Letter, we propose a methodology to constrain the Hubble constant $H_0$ by incorporating the TDE parameters measured by EM observations (e.g., stellar mass, black hole (BH) mass and spin, and other orbital parameters) into the observed TDE GW waveforms. We argue that an accurate knowledge of the BH spin could help constrain the orbital inclination angle, hence alleviating the well-known distance-inclination degeneracy in GW waveform fitting. For individual TDEs, the precise redshift measurement of the host galaxies along with the luminosity distance $D_{\rm L}$ constrained by EM and GW signals would give a self-contained measurement of $H_0$ via Hubble's law, completely independent of any specific cosmological models.