April 1
Transient Accretion onto Supermassive Black Holes
Speaker: Megan Masterson, PhD student, MIT
Abstract: Our expectations for how matter accretes onto supermassive black holes (SMBHs) are rapidly evolving in the era of time-domain astrophysics. Despite decades of work on SMBH accretion, these time-domain surveys are revealing that accreting SMBHs can be more variable and extreme than we previously thought. To showcase the extremes of the inner accretion flow, I will present results from a multi-year X-ray campaign on a particularly dramatic accreting SMBH, 1ES 1927+654. In 2022, this source recently began showing an X-ray quasi-periodic oscillation (QPO) with significant frequency evolution – a discovery that has implications for corona-jet coupling in SMBHs and prospects for next-generation X-ray and gravitational wave synergies. I will also highlight time-domain studies of dormant SMBHs, namely the importance of using infrared observations to uncover the full census of tidal disruption events (TDEs) and the prospect of using JWST observations of TDEs to probe the nuclear environments of dormant SMBHs. Finally, I will end by highlighting how the Vera Rubin Observatory and the Nancy Grace Roman Space Telescope promise to transform the field in the next few years.
Host: Robert Stein & Lia Hankla