Speaker
Description
In the last five years, a mysterious new class of astrophysical transients have been uncovered using primarily X-ray telescopes. These sources are spatially coincident with centers of galaxies and show X-ray variations that repeat with quasi–periodicities on timescales of minutes to ~ a few years. One of the prevailing ideas for these Repeating Extragalactic Nuclear Transients (RENTs) is that they are triggered by interactions of a gravitationally bound (smaller) object with the accretion disk of a supermassive black hole (SMBH). If that is indeed the case, then some of these extreme mass ratio binaries could also be detectable with future space-based gravitational wave detectors like LISA and Taiji, and have the potential to transform our understanding of supermassive black hole growth, probe dark energy, and put fundamental constraints on gravity. I will present an observational overview of RENTs, their connection to stellar tidal disruption events and also present some state-of-the-art general relativistic hydrodynamic simulations of objects embedded in SMBH disks and argue that, in some cases, these repeating transients could be double compact object binaries with direct implications for multi-messenger astrophysics. I will highlight the critical roles of Swift/XRT and UVOT in transforming our understanding of RENTs, and will end by highlighting the exciting prospects of discovering more such systems with synergy between the Rubin/LSST observatory and various space-based X-ray, IR and UV telescopes.
