Modeling maximum astrophysical gravitational recoil velocities

TL;DR

This paper models the maximum gravitational recoil velocities in black-hole mergers, revealing linear and higher-order spin effects, and predicts a maximum recoil velocity of approximately 3680 km/s.

Contribution

It provides a detailed analysis of recoil velocities as a function of spin, including higher-order corrections, and offers a new prediction for the maximum recoil velocity.

Findings

Recoil velocity depends linearly on spin and angle cosine.

Higher-order spin and angle corrections are significant.

Maximum recoil velocity predicted as 3680±130 km/s.

Abstract

We measure the recoil velocity as a function of spin for equal-mass, highly-spinning black-hole binaries, with spins in the orbital plane, equal in magnitude and opposite in direction. We confirm that the leading-order effect is linear in the spin and the cosine of angle between the spin direction and the infall direction at merger. We find higher-order corrections that are proportional to the odd powers in both the spin and cosine of this angle. Taking these corrections into account, we predict that the maximum recoil will be 3680+-130 km/s.