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arXiv · 0811.3583

A probable giant planet imaged in the Beta Pictoris disk

A. -M. Lagrange·D. Gratadour·G. Chauvin·T. Fusco·D. Ehrenreich·D. Mouillet·G. Rousset·D. Rouan·F. Allard·E. Gendron·J. Charton·L. Mugnier·P. Rabou·J. Montri·F. Lacombe
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Abstract

Since the discovery of its dusty disk in 1984, Beta Pictoris has become the prototype of young early-type planetary systems, and there are now various indications that a massive Jovian planet is orbiting the star at ~ 10 AU. However, no planets have been detected around this star so far. Our goal was to investigate the close environment of Beta Pic, searching for planetary companion(s). Deep adaptive-optics L'-band images of Beta Pic were recorded using the NaCo instrument at the Very Large Telescope. A faint point-like signal is detected at a projected distance of ~ 8 AU from the star, within the North-East side of the dust disk. Various tests were made to rule out with a good confidence level possible instrumental or atmospheric artifacts. The probability of a foreground or background contaminant is extremely low, based in addition on the analysis of previous deep Hubble Space Telescope images. The object L'=11.2 apparent magnitude would indicate a typical temperature of ~1500 K and a mass of ~ 8 Jovian masses. If confirmed, it could explain the main morphological and dynamical peculiarities of the Beta Pic system. The present detection is unique among A-stars by the proximity of the resolved planet to its parent star. Its closeness and location inside the Beta Pic disk suggest a formation process by core accretion or disk instabilities rather than a binary-like formation process.

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A. -M. Lagrange, D. Gratadour, G. Chauvin, T. Fusco, D. Ehrenreich, D. Mouillet, G. Rousset, D. Rouan, F. Allard, E. Gendron, J. Charton, L. Mugnier, P. Rabou, J. Montri, F. Lacombe. 2008-11-21. A probable giant planet imaged in the Beta Pictoris disk. https://doi.org/10.1051/0004-6361%3A200811325

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