2010/09/01 by O. Absil, Olivier Absil, J.-B. Le Bouquin +15 · 1 citation
Physics and Astronomy · #Angular diameter #Angular resolution (graph drawing) #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Binary number #Binary star #Brown dwarf #Interferometry #Planetary system #Resolution (logic) #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1051/0004-6361/201015156
5 pages, 4 figures. Accepted for publication in A&A Letters
openalex publication_date 2010/09/01 · arxiv created 2010/09/07 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
<i>Aims. <i/>We search for low-mass companions in the innermost region (<300 mas, i.e., 6 AU) of the <i>β<i/> Pic planetary system.<i>Methods. <i/>We obtained interferometric closure phase measurements in the <i>K<i/>-band with the VLTI/AMBER instrument used in its medium spectral resolution mode. Fringe stabilization was provided by the FINITO fringe tracker.<i>Results. <i/>In a search region of between 2 and 60 mas in radius, our observations exclude at 3<i>σ<i/> significance the presence of companions with <i>K<i/>-band contrasts greater than 5×10<sup>-3<sup/> for 90% of the possible positions in the search zone (i.e., 90% completeness). The median 1<i>σ<i/> error bar in the contrast of potential companions within our search region is 1.2×10<sup>-3<sup/>. The best fit to our data set using a binary model is found for a faint companion located at about 14.4 mas from <i>β<i/> Pic, which has a contrast of 1.8×10<sup>-3<sup/> <i>±<i/> 1.1×10<sup>-3<sup/> (a result consistent with the absence of companions). For angular separations larger than 60 mas, both time smearing and field-of-view limitations reduce the sensitivity.<i>Conclusions. <i/>We can exclude the presence of brown dwarfs with masses higher than 29 <i>M<i/><sub>Jup<sub/> (resp. 47 <i>M<i/><sub>Jup<sub/>) at a 50% (resp. 90%) completeness level within the first few AUs around <i>β<i/> Pic. Interferometric closure phases offer a promising way to directly image low-mass companions in the close environment of nearby young stars.