| Description |
We have recently used Spitzer to confirm that large IR excesses seen
in about 20-30% of old close binary stars by IRAS correspond to very
warm close-in dust that appears to originate from recent collisions of
planets or planetesimals (Matranga et al. 2010). Somehow, close binaries
seem to be destabilizing their planetary progeny, perhaps through
secular shrinkage of the stellar separation caused by magnetically-driven
angular momentum loss. The aim of this proposal is to use Herschel to
search for excesses characteristic of Kuiper-belt-like cold dust or
planetesimals in a sample of 88 close binaries from an approved
Spitzer IRAC survey. Probing these larger radii in such systems will
provide a robust sample of broad SEDs to understand debris disks in
close binaries, provide insight into the possibly origin of the Earth mass
or more of dust required, and give us a unique handle in understanding
planetary formation in circumbinary disks. |
