Searching for bright compact needles in a radio haystack of galaxies and stars

The discovery of fast radio bursts (FRBs) is one of the most intriguing radio astronomical discoveries of our time. FRBs are short (faster than the blink of an eye) and energetic (as much energy in a few milliseconds as the Sun outputs in a day) radio flashes originating from outside our Milky Way galaxy. The nature of FRBs remains elusive, but causality arguments based on the short duration of these bursts imply a compact origin. Furthermore, a detection of FRB-like emission from the Galactic magnetar SGR 1935+2154 hints towards a neutron star origin. From the handful of FRBs that have been localized to a host galaxy, two published cases have been associated with compact, persistent radio sources (PRSs). Both display a characteristic broadband synchrotron spectrum and both dwarf galaxies (containing less than about three billion solar masses), sharing similarities with intermediate-mass black hole (IMBH, 100 to 100,000 solar masses) candidates. To further our understanding of the role of PRSs in the lifecycle of FRBs, and potentially black hole growth, it is crucial to discover more of them.