Golden galactic binaries for LISA: mass-transferring white dwarf black hole binaries

TL;DR

This paper models white dwarf--black hole binaries' evolution and gravitational wave signals, revealing universal relations that enable mass and distance estimation with LISA, opening new avenues for binary population studies.

Contribution

It introduces new universal relations for white dwarf--black hole binaries, facilitating mass and distance inference from gravitational wave data.

Findings

Universal relations between masses and GW frequency derivatives

Potential for LISA to detect and characterize these binaries

Mass and distance estimation capabilities with high precision

Abstract

We study the evolution and gravitational wave emission of white dwarf -- black hole accreting binaries with a semi-analytical model. These systems will evolve across the mHz gravitational wave frequency band and potentially be detected by the Laser Interferometer Space Antenna (LISA). We identify new universal relations for this class of binaries, which relate the component masses to the gravitational wave frequency and its first derivative. Combined with the high precision measurements possible with LISA, these relations could allow us to infer the component masses and the luminosity distance of the source. LISA has therefore the potential to detect and characterize a virtually unexplored binary population.