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

Authors

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

Affiliations

Université de Liège LAOG MPIA Heidelberg

Abstract

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
PDF, 1.2 Mb