Are stellar-mass black-hole binaries too quiet for LISA?

Abstract

The progenitors of the high-mass black-hole mergers observed by LIGO and Virgo are potential LISA sources and promising candidates for multiband GW observations. In this letter, we consider the minimum signal-to-noise ratio these sources must have to be detected by LISA. Our revised threshold of ${\rho }_{\mathrm{thr}}\sim 15$ is higher than previous estimates, which significantly reduces the expected number of events. We also point out the importance of the detector performance at high-frequencies and the duration of the LISA mission, which both influence the event rate substantially.

6 pages, 3 figures. Published in MNRAS letters. DOI 10.1093/mnrasl/slz104