Searching for ultralight bosons within spin measurements of a population of binary black hole mergers

Ultralight bosons can form clouds around rotating black holes if their Compton wavelength is comparable to the hole size. The boson cloud spins down through a process called superradiance, lowering spin characteristic value. It has been suggested that measurements of detected by ground-based gravitational-wave detectors be used constrain mass ultralight bosons. Unfortunately, measurement individual often uncertain, resulting in inconclusive results. Instead, we use hierarchical Bayesian inference combine information from multiple sources and obtain stronger constraints. We show hundreds high signal-to-noise ratio detections are enough exclude (confirm) existence non-interacting range $\left[10^{-13},3\times 10^{-12}\right]~\rm{eV}$ $\left([10^{-13},10^{-12}]~\rm{eV}\right)$. precise number depends on distribution at formation boson. From few uninformative binary mergers LIGO Virgo first two observing runs, cannot draw statistically significant conclusions.