The Tidal Disruption Process For a White Dwarf and a Massive Black Hole

The tidal disruption of a star can serve as a diagnostic for the presence of a dormant black hole in a distant galaxy.  While such tidal disruption events are rare, they give rise to powerful flares of emission at and above Eddington luminosity, with spectral features and timescales that might reveal both the type of star and the mass (and perhaps spin) of the black hole.  In our study, we consider relativistic encounters between white dwarfs and massive black holes at the threshold of disruption.  We develop a numerical code whose central feature is the use of Fermi normal coordinates (FNC).  We characterize the mass loss from the star and provide a detailed view into the (hydro)dynamics of the remnant and debris.  In this talk, I will discuss these results and present a hybrid approach that relies on the FNC method in combination with fully general relativistic hydrodynamics to model the early accretion of debris onto the black hole with high accuracy. This new and timely development in tidal disruption studies is directly motivated by the anticipated abundance of data from the current and upcoming multi-wavelength surveys of the transient sky.