Scientific Colloquium
March 8, 2013


"Supermassive Black Hole Caught Red Handed in Stellar Homicide"

It was first proposed by theorists in the late 1970's that an inevitable
consequence of a massive black hole lurking in the center of a galaxy is that
stars will pass close enough to the black hole to be ripped apart by its extreme
tidal forces and consumed.  Rees (1988) suggested that the luminous flare of
radiation from the accretion of the bound tidal debris could be used as a
signpost for an otherwise dormant and undetectable black hole.  The first
observational tidal disruption event candidates emerged in the late 1990's from
an archival search of the ROSAT All-Sky Survey, in the form of luminous soft
X-ray outbursts from several otherwise inactive galaxies.  Since then, about a
dozen tidal disruption event candidates have been discovered across the
electromagnetic spectrum. I will review these candidates, and highlight our most
recent discovery in which there was enough information from the crime scene
(observations) to determine both the victim (chemical composition and structure
of the star) and the identity of the perpetrator (black hole mass). I will
conclude with the promising detection rates of the next generation of time
domain surveys, and how large samples of these events can be used as transient
probes of accretion physics, jet formation, and black hole demographics. 
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