A VLTI/AMBER closure-phase search for low-mass companions around nearby young stars: first results on beta Pictoris


O. Absil, J.-B. Le Bouquin, G. Chauvin, C. Hanot, M. Benisty, J.-C. Augereau, J. Lebreton


Université de Liège LAOG MPIA Heidelberg


Young stars in nearby moving groups and associations are well suited to search for low-mass companions. In addition to their brightness, their proximity gives access to small linear separations and their youth makes potential low-mass companion brighter than around older main sequence stars. We have recently started a survey of such young nearby stars with the AMBER near-infrared interferometer at the VLTI. The closure phase measurements provided by AMBER on a triplet of baselines are particularly sensitive to nearby off-axis point-like sources. In this talk, we describe the first results of this survey obtained on beta Pictoris. Thanks to a closure phase accuracy of a few 0.1 degree, we show that a 3-sigma sensitivity of about 4e-3 can be reached on the contrast of potential companions for angular separations between 0.01 and 0.2 arcsec. This translates into a companion mass of about 35 Mjup from 0.2 to 4 AU in the case of beta Pictoris. We extrapolate this result on other stars of our survey and discuss the discovery space of AMBER.

Attached documents

Lyot2010proc s2 talk AbsilO.pdf
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