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An Upper Limit to the Mass of rho1 Cnc's Radial Velocity Companion

Melissa A. McGrath·Edmund Nelan·David C. Black·George Gatewood·Keith Noll·Al Schultz·Stephen Lubow·Inwoo Han·Tomasz F. Stepinski·Thomas Targett
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Abstract

Doppler spectroscopy of rho1 Cnc has detected evidence of a companion with an orbital period of 14.65 days and a minimum mass of 0.88 Jupiter masses. Astrometric observations performed with the Hubble Space Telescope Fine Guidance Sensor 1r using a novel new observing technique have placed an upper limit on the astrometric reflex motion of rho1 Cnc in a time period of only one month. These observations detected no reflex motion induced by the 14.65 day period radial velocity companion, allowing us to place a 3-sigma upper limit of \~0.3 milliarcseconds on the semi-major axis of this motion, ruling out the preliminary Hipparcos value of 1.15 milliarcseconds. The corresponding upper limit on the true mass of the companion is ~30 Mj, confirming that it is a sub-stellar object.

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Melissa A. McGrath, Edmund Nelan, David C. Black, George Gatewood, Keith Noll, Al Schultz, Stephen Lubow, Inwoo Han, Tomasz F. Stepinski, Thomas Targett. 2001-12-03. An Upper Limit to the Mass of rho1 Cnc's Radial Velocity Companion. https://arxiv.org/abs/astro-ph/0112036

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