Context: Since the discovery of its dusty disk in 1984,
Aims: Our goal was to investigate the close environment of β Pic, searching for planetary companion(s).
Methods: Deep adaptive-optics L'-band images of β Pic were recorded using the NaCo instrument at the Very Large Telescope.
Results: A faint point-like signal is detected at a projected distance of ≃8 AU from the star, within the northeastern extension of the dust disk. Various tests were made to rule out possible instrumental or atmospheric artefacts at a good confidence level. The probability of a foreground or background contaminant is extremely low, based in addition on the analysis of previous deep HST images. Its L'=11.2 apparent magnitude would indicate a typical temperature of ~1500 K and a mass of ~8 M_Jup. If confirmed, it could explain the main morphological and dynamical peculiarities of the β 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 β Pic disk suggest a formation process by core accretion or disk instabilities rather than binary-like formation processes.
Astronomy and Astrophysics
- Pub Date:
- January 2009
- instrumentation: adaptive optics;
- stars: early-type;
- stars: planetary systems;
- stars: individual: β Pic;
- 5 pages, 3 figures, 1 table. A&