Gravitational Collider Physics via Pulsar-Black Hole Binaries II: Fine and Hyperfine Structures are Favored

TL;DR

This paper proposes that fine and hyperfine structure transitions in gravitational atoms formed by black holes and light bosons, when paired with pulsars, are promising and analytically tractable signals for detecting superradiance effects.

Contribution

It demonstrates that fine and hyperfine transitions are more detectable and better understood analytically than Bohr transitions in pulsar-black hole systems for gravitational collider signals.

Findings

Fine and hyperfine transitions are more likely to be observed than Bohr transitions.

These transitions are more analytically accessible for detection.

Pulsar timing can potentially reveal superradiance-induced structures.

Abstract

A rotating black hole can be clouded by light bosons via superradiance, and thus acquire an atom-like structure. If such a gravitational atom system is companioned with a pulsar, the pulsar can trigger transitions between energy levels of the gravitational atom, and these transitions can be detected by pulsar timing. We show that in such pulsar-black hole systems, fine and hyperfine structure transitions are more likely to be probed than the Bohr transition. Also, the calculation of these fine and hyperfine structure transitions are under better analytic control. Thus, these fine and hyperfine structure transitions are more ideal probes in the search for gravitational collider signals in pulsar-black hole systems.