Spinning boson stars and Kerr black holes with scalar hair: the effect of self-interactions

TL;DR

This paper investigates how scalar self-interactions influence the physical characteristics of spinning boson stars and Kerr black holes with scalar hair, highlighting changes in compactness, ergo-regions, and scalar field configurations.

Contribution

It provides new insights into the effects of scalar self-interactions on spinning boson stars and Kerr black holes with scalar hair, expanding understanding of their physical properties.

Findings

Self-interacting boson stars are less compact than non-self-interacting ones.

Scalar self-interactions affect the occurrence of ergo-regions.

The properties of Kerr black holes with scalar hair are influenced by scalar self-interactions.

Abstract

Self-interacting boson stars have been shown to alleviate the astrophysically low maximal mass of their non-self-interacting counterparts. We report some physical features of spinning self-interacting boson stars, namely their compactness, the occurence of ergo-regions and the scalar field profiles, for a sample of values of the coupling parameter. The results agree with the general picture that these boson stars are comparatively less compact than the non-self-interacting ones. We also briefly discuss the effect of scalar self-interactions on the properties of Kerr black holes with scalar hair.