Imaging Young Stellar Objects with AMBER on the VLTI

摘要

Young Stellar Objects (YSOs) play a central role in the understanding of stellar and planet formation, and progress in spatial resolution and sensitivity of long infrared interferometers made such instruments particularly well suited to probe the inner part of the disk where essential physical processes and interactions are believed to take place. The first astrophysical results obtained on young stars arising from this technique are already giving a handful of informations about the structure of the extended component. However, model-fitting methods used to reduce the data prevent from definitive and unambiguous interpretations. Interferometric observations of Herbig Ae/Be stars is one of the most striking example. Whereas first results seemed to be in good agreement with accretion disk model, latest observations tend to favor the presence of a uniform ring with a inner radius set by dust sublimation temperature. Direct imaging of close environments around YSOs with infrared (IR) interferometers will allow to disentangle between current suggested models and to improve one step further the scenarios of stellar formation. Within this framework, we anticipate observations of YSOs with the VLTI and we investigate the potential of AMBER to recover images. Modelling their circumstellar environment, we simulate realistic observations of Herbig Ae/Be and TTauri stars. By using reconstruction technique specially dedicated to infrared interferometry and to sparse (u, v) data coverage, we analyze the quality of the recovered images, and we emphasize the critical points to take into account in the image reconstruction process. We conclude that it requires at least three nights of observations to perform imaging of YSOs with AMBER on the VLTI.