Limits on Planets Around White Dwarf Stars

F. Mullally; D. E. Winget; Steven Degennaro; Elizabeth Jeffery; S. E. Thompson; Dean Chandler

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arXiv · 0801.3104

Limits on Planets Around White Dwarf Stars

F. Mullally·D. E. Winget·Steven Degennaro·Elizabeth Jeffery·S. E. Thompson·Dean Chandler

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Abstract

We present limits on planetary companions to pulsating white dwarf stars. A subset of these stars exhibit extreme stability in the period and phase of some of their pulsation modes; a planet can be detected around such a star by searching for periodic variations in the arrival time of these pulsations. We present limits on companions greater than a few Jupiter masses around a sample of 15 white dwarf stars as part of an on-going survey. One star shows a variation in arrival time consistent with a 2 M_J planet in a 4.5 year orbit. We discuss other possible explanations for the observed signal and conclude that a planet is the most plausible explanation based on the data available.

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F. Mullally, D. E. Winget, Steven Degennaro, Elizabeth Jeffery, S. E. Thompson, Dean Chandler. 2008-01-20. Limits on Planets Around White Dwarf Stars. https://arxiv.org/abs/0801.3104

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