High-mass star formation expored with maser VLBI & thermal (ALMA, JVLA) observations
2019 February 18
Intense methanol and water maser transitions are commonly observed towards high-mass young stellar objects (YSO). Multi-epoch very long baseline interferometry (VLBI) observations allow us to determine maser positions and three-dimensional velocities with an accuracy of about 1 mas and 1 km/s, respectively. Presently, JVLA cm and ALMA mm observations can determine the spatial distribution and (line of sight) kinematics of the thermal (continuum and line) emission around the forming star with unprecedented sensitivity (~10 microJy and ~1 mJy for continuum and line, respectively) and angular resolution (0.05" - 0.2"). Combining maser VLBI and thermal interferometric datasets is the most accurate way to determine the physical conditions and unveil the dynamical structures (disks, jets, expanding/infalling shells) associated with massive star formation. This talk presents the results of this technique for two massive star-forming regions: G16.59-0.05 and G24.78+0.08, whose maser emission has been extensively monitored with VLBI and for which we have recently obtained new JVLA and ALMA data.