Nathaniel Roth is a JSI Fellow who studies super-massive black holes using radiative transfer calculations. He is particularly interested in the tidal disruption of individual stars by these black holes, and using the resulting emission to learn about the hydrodynamics of accretion and black hole demographics.
As tidal disruption events (TDEs) of stars by super-massive black holes are detected at an ever-increasing rate, we are learning just how rich the range of outcomes in these events can be. While they share a core set of observational properties, they exhibit dramatic differences when followed up in detail. This information may prove useful for learning about the black holes and stars that are involved, but we still lack an understanding of how to connect various disruption scenarios to the lightcurves and spectra we see. I will summarize the rapidly growing TDE dataset, and then discuss radiative transfer calculations aimed at understanding the range of x-ray, UV and optical spectral signatures that have been seen. In particular, I will discuss evidence indicating that in many events a large fraction of the stellar debris is launched in an outflow, and connect this to models of super-Eddington accretion.