Over the last few years, X-ray and optical observations have hinted at the existence of black holes in a new mass range: hundreds to thousands of solar masses, the so-called intermediate-mass black holes. Many of the best candidates appear associated with dense stellar clusters, where there are many interactions that could generate detectable gravitational radiation. Indeed, these are one of the rare classes of sources for which rigorous proof of their existence may require detection of gravitational waves. This focus session's goal is to explore the interplay between the astrophysics and the gravitational wave physics of intermediate-mass black holes, from cosmology and cluster dynamics to probes of the Kerr spacetime. The framing questions are:
What is the current evidence for the existence of intermediate-mass black holes and their environments, and what are the scenarios in which they emit gravitational radiation?
What are the proposed mechanisms for the formation of intermediate-mass black holes, and what implications do these have for gravitational wave observations?
What information about astrophysics or fundamental physics could be derived from observations of gravitational radiation from intermediate-mass black holes?
What realistic additions or modifications to detectors would optimize the search for gravitational waves from intermediate-mass black holes?