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Speaker: Megan Newsome | UCSBDate/Time: June 7, 2024 / 12 noon central.Location: 134 Astronomy Building.Zoom: https://go.illinois.edu/AstroColloquiumTitle: Unveiling Supermassive Black Hole Environments with Tidal Disruption EventsAbstract: When stars approach the tidal radius of a supermassive black hole (SMBH) and find themselves unraveled, the resulting debris stream spirals toward the SMBH and creates a flare whose light can outshine the host galaxy. TDEs have recently offered us glimpses into the sub-parsec local environments near SMBHs. AT 2020mot is a typical UV/optical TDE, but is uniquely bright in the near-infrared and even shows a later enhancement in brightness along the tail of the light curve. This could be the first TDE to show two "dust echoes," indicative of concentric rings of thin dust within 0.1 parsecs of a SMBH, among the smallest scales at which dust has been inferred near SMBHs. Similarly, the event AT 2022upj is an extreme coronal line emitter (ECLE) that shares emission line diagnostics in common with the small subset of ECLEs believed to be "light echoes" of TDEs in gas-rich environments. Events like AT 2020mot and AT 2022upj are novel opportunities to peer into the closest material of otherwise invisible black holes in quiet galaxies. Studying these events will explore the fundamental connections between supermassive black holes, galaxy evolution, and accretion mechanics.