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arXiv · 1205.0806

Precision Astrometry of the Exoplanet Host Candidate GD 66

J. Farihi·J. P. Subasavage·E. P. Nelan·H. C. Harris·C. C. Dahn·J. Nordhaus·D. S. Spiegel
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Abstract

The potential existence of a giant planet orbiting within a few AU of a stellar remnant has profound implications for both the survival and possible regeneration of planets during post-main sequence stellar evolution. This paper reports Hubble Space Telescope Fine Guidance Sensor and U.S. Naval Observatory relative astrometry of GD 66, a white dwarf thought to harbor a giant planet between 2 and 3 AU based on stellar pulsation arrival times. Combined with existing infrared data, the precision measurements here rule out all stellar-mass and brown dwarf companions, implying that only a planet remains plausible, if orbital motion is indeed the cause of the variations in pulsation timing.

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J. Farihi, J. P. Subasavage, E. P. Nelan, H. C. Harris, C. C. Dahn, J. Nordhaus, D. S. Spiegel. 2012-05-03. Precision Astrometry of the Exoplanet Host Candidate GD 66. https://doi.org/10.1111/j.1365-2966.2012.21221.x

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