Characterizing the Ionized Gas around Massive Protostars

• Applicant: Dr. Alberto Sanna, Ph.D.
• Subject Area: Astrophysics and Astronomy
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 263099539

Massive stars play a dominant role in terms of their influence on the energetics and chemical budget of the Galactic Interstellar Medium (ISM). At an early stage of stellar evolution, massive young stellar objects (YSOs) inject large amounts of mechanical energy into the ISM by powerful outflow phenomena, which are a main outcome of mass accretion onto the protostar. In turn, this outflow activity provide a major source of turbulent energy for the cluster gas. In this context, it is fundamental to properly characterize the dynamical interaction between massive YSOs and their surrounding envelopes over a wide range of spatial scales and physical phenomena. Here, I propose to systematically quantify the energetics (i.e., momentum flux and mechanical luminosity) injected by massive forming stars into the ISM at their early stages of evolution, focusing on spatial scales on the order of 1000 AU. I propose to achieve this goal by means of high-resolution and high-sensitivity Jansky Very Large Array (JVLA) observations of the hyper-compact radio continuum emission of a robust sample (40) of massive YSOs. These radio continuum observations in 3 spectral bands (from 6 to 22 GHz), and with an angular resolution of about 0.1 arcsec, have already been granted by the JVLA time allocation committee (about 60 hr) and will be concluded by September 2014.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1573: Physics of the Interstellar Medium
• International Connection: Italy, Netherlands
• Participating Persons: Professor Dr. Ricardo Cesaroni; Dr. Ciriaco Goddi; Professor Dr. Karl M. Menten; Dr. Luca Moscadelli; Dr. Alvaro Sanchez-Monge