Renormalized spin coefficients in the accumulated orbital phase for unequal mass black hole binaries

TL;DR

This paper develops a method to incorporate third post-Newtonian effects into the orbital phase calculations of unequal mass black hole binaries by renormalizing spin contributions, improving gravitational wave modeling.

Contribution

It introduces a novel renormalization technique for spin coefficients to account for 3PN effects in gravitational wave phase evolution.

Findings

Enhanced accuracy in orbital phase modeling for black hole mergers.

Better representation of spin precession effects in gravitational wave signals.

Applicable to systems with mass ratios around 1/10.

Abstract

We analyze galactic black hole mergers and their emitted gravitational waves. Such mergers have typically unequal masses with mass ratio of the order 1/10. The emitted gravitational waves carry the inprint of spins and mass quadrupoles of the binary components. Among these contributions, we consider here the quasi-precessional evolution of the spins. A method of taking into account these third post-Newtonian (3PN) effects by renormalizing (redefining) the 1.5 PN and 2PN accurate spin contributions to the accumulated orbital phase is developed.