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arXiv · astro-ph/0511679

A Massive Planet to the Young Disc Star HD 81040

A. Sozzetti·S. Udry·S. Zucker·G. Torres·J. L. Beuzit·D. W. Latham·M. Mayor·T. Mazeh·D. Naef·C. Perrier·D. Queloz·J. -P. Sivan
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Abstract

We report the discovery of a massive planetary companion orbiting the young disc star HD 81040. Based on five years of precise radial-velocity measurements with the HIRES and ELODIE spectrographs, we derive a spectroscopic orbit with a period $P =1001.0$ days and eccentricity $e = 0.53$. The inferred minimum mass for the companion of $m_2\sin i = 6.86$ M$_\mathrm{Jup}$ places it in the high-mass tail of the extrasolar planet mass distribution. The radial-velocity residuals exhibit a scatter significantly larger than the typical internal measurement precision of the instruments. Based on an analysis of the Ca II H and K line cores, this is interpreted as an activity-induced phenomenon. However, we find no evidence for the period and magnitude of the radial-velocity variations to be caused by stellar surface activity. The observed orbital motion of HD 81040 is thus best explained with the presence of a massive giant planet companion.

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A. Sozzetti, S. Udry, S. Zucker, G. Torres, J. L. Beuzit, D. W. Latham, M. Mayor, T. Mazeh, D. Naef, C. Perrier, D. Queloz, J. -P. Sivan. 2005-11-23. A Massive Planet to the Young Disc Star HD 81040. https://doi.org/10.1051/0004-6361%3A20054303

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