Institute of Astronomy

The Origin and Dynamics of Dusty Disks Around White Dwarfs

SpeakerTalk DateTalk Series
John Debes30 July 2014Across HR 2014 Talks


As the final endpoint of stellar evolution, at first glance white dwarfs don’t appear to be fertile grounds for the study of exoplanetary systems.  Over the past twenty-seven years however, evidence has mounted that a significant fraction of white dwarfs might be hosts to relic planetary systems.  The observable signatures planets are most easily detected as either an infrared excess due to dust orbiting a few tens of white dwarf radii away or through the presence of photospheric metal lines--both signatures of tidally disrupted minor bodies perturbed by larger planets into highly eccentric orbits.  In this talk I will review the various observations of the dust component around WDs and link them to our understanding of the late stages of planetary system evolution.  Firmly establish- ing this link is crucial for interpreting the composition of WD dust.