Antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) radio interferometer located in the Atacama Desert, Chile. The antennas are positioned on the Chajnantor plateau, at an altitude of over 5,000 meters, an ideal location for astronomy thanks to its dry and thin atmosphere. The Milky Way, our galaxy, is visible in the sky above the antennas, along with other astronomical features such as the Magellanic Clouds. Credits: Eso.org
Luigi Zallio
Abstract
ALMA line surveys offer a unique opportunity to study large populations of protoplanetary disks with low integration times per source.
However, classic image-plane analyses are limited in their ability to accurately extract bulk gas disk properties (i.e. sizes and fluxes) from the resulting moderate angular resolution data.
In this talk, I present measurements of key disk properties inferred from parametric modeling of ALMA Band 7 12CO (J=3-2) spectral line visibilities. From these models, I derive stellar masses, gas-disk radii, integrated fluxes, optically thick emission layers, and brightness temperature profiles for the disk population in the old (4–14 Myr) Upper Scorpius star-forming region, using moderate angular resolution observations (0.1–0.3″).
Furthermore, I use the disk-based stellar masses derived from my analysis to benchmark pre-main-sequence evolutionary tracks, and I show how these masses can be used to obtain more precise stellar ages.