Beyond the Bowen-York extrinsic curvature for spinning black holes

TL;DR

This paper explores methods to reduce spurious radiation in initial data for spinning black holes, demonstrating improvements using the puncture approach for Kerr black holes in binary collisions.

Contribution

It introduces an approach to minimize junk radiation in spinning black hole initial data by applying the puncture method to Kerr black holes.

Findings

Spurious radiation increases with black hole spin in Bowen-York data.

Applying the puncture approach to Kerr black holes reduces junk radiation.

Effective for head-on black hole collisions with equal masses.

Abstract

It is well-known that Bowen-York initial data contain spurious radiation. Although this ``junk'' radiation has been seen to be small for non-spinning black-hole binaries in circular orbit, its magnitude increases when the black holes are given spin. It is possible to reduce the spurious radiation by applying the puncture approach to multiple Kerr black holes, as we demonstrate for examples of head-on collisions of equal-mass black-hole binaries.