Dynamical Masses of Young Stellar Multiple Systems

with the VLBA (DYNAMO-VLBA)

As part of our previous Very Long Baseline Array (VLBA) observations, we unveiled a significant number of tight binary and multiple Young Stellar Objects (YSOs), whose components have detectable radio emission. The typical separation of the components in these systems is of the order of 10 milli-arcseconds, thus Gaia will not provide information on their orbital parameters and VLBA observations will be an excellent tool to keep studying them. In fact, by monitoring their stellar motion using muti-epoch observations, for a few of them we were able to determine their orbital parameters and to estimate their dynamical mass. However, for the majority of these objects more observations are required and the DYNAMO-VLBA project (VLBA/BD215) will obtain them.

The Goal of DYNAMO-VLBA is to determine the dynamical masses for an unprecedent number of YSOs in different star forming regions. DYNAMO-VLBA will provide an outstanding sample of YSOs with measured dynamical masses to test evolutionary models of premain-sequence stars. In general, it will also show that radio-astrometry is a key technique that will keep contributing to the understanding of YSOs and the early stages of star formation even in the Gaia era.