PI: Jay Farihi, University of Cambridge, firstname.lastname@example.org
Address: Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK
CoI: Jay Holberg, University of Arizona
CoI: Seth Redfield, Wesleyan University
CoI: Boris Gansicke, University of Warwick
Title: The Bulk Composition of Rocky Planetary Debris and a Search for Water
Abstract: We propose medium-resolution spectroscopy to measure the abundances of several trace heavy elements in a sample of externally-polluted, cool, He atmosphere white dwarfs discovered in the Sloan Digital Sky Survey. Both \em Spitzer and ground-based studies have now firmly connected metal-rich white dwarfs with closely orbiting, rocky debris that likely results from the tidal disruption of one or more minor planets. With steady-state and time-dependent models for the atmospheric, heavy element pollution, the proposed observations will indirectly determine the bulk composition of the accreted planetary material. Spectroscopy of metal-contaminated white dwarfs constrains the frequency and bulk composition of exo-terrestrial planetary bodies at intermediate mass stars; no other technique has this power. Importantly, the proposed experiment has the potential to identify water- rich, rocky parent bodies via oxygen detected in excess of that expected for mineral oxides, and thus has implications for habitable planet building in the Galaxy.
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