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arXiv · 0909.2038

Limits on Unresolved Planetary Companions to White Dwarf Remnants of 14 Intermediate-Mass Stars

Mukremin Kilic·Andrew Gould·Detlev Koester
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Abstract

We present Spitzer IRAC photometry of white dwarf remnants of 14 stars with M = 3-5 Msol. We do not detect mid-infrared excess around any of our targets. By demanding a 3 sigma photometric excess at 4.5 micron for unresolved companions, we rule out planetary mass companions down to 5, 7, or 10 M_J for 13 of our targets based on the Burrows et al. (2003) substellar cooling models. Combined with previous IRAC observations of white dwarf remnants of intermediate-mass stars, we rule out \geq 10 M_J companions around 40 white dwarfs and \geq 5 M_J companions around 10 white dwarfs.

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Mukremin Kilic, Andrew Gould, Detlev Koester. 2009-09-10. Limits on Unresolved Planetary Companions to White Dwarf Remnants of 14 Intermediate-Mass Stars. https://doi.org/10.1088/0004-637x/705/2/1219

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