Sydney CPPC Seminar 3rd March 2022
Ling Sun (ANU): Probing ultralight bosons with black holes and gravitational waves
Ultralight boson particles, if they exist as theorized, could form clouds around rapidly rotating black holes through the phenomenon called superradiance. Such clouds are expected to emit continuous, quasimonochromatic gravitational waves that could be detected by gravitational-wave detectors like LIGO and Virgo. Searching for gravitational waves emitted by boson clouds around black holes provides a new cosmic approach to interrogating the existence of ultralight bosons that are difficult to probe with conventional lab experiments. Analyses have been conducted using data collected in recent observing runs of Advanced LIGO, yielding interesting constraints on the properties of these yet-undiscovered particles. In this talk, I will provide a brief theoretical overview of the phenomenon and signal model, discuss the astrophysical sources, and present the highlighted results from recent analyses. The future ground-based detector network with improved sensitivity as well as space-based gravitational-wave detectors will promise the capability of probing a large parameter space of the ultralight bosons, or even a direct detection.