Zooming in on the Chemistry of Protoplanetary Disks with ALMA

Abstract

During the first few ~Myr of a young stars life, it is encircled by a disk made up of molecular gas, dust, and ice – the building blocks for future planetary systems. How/when these disks form planets and what sets the planets initial compositions remain key outstanding questions in disk science. In recent years, major leaps in sensitivity and spatial resolution afforded by the Atacama Large Millimeter/Submillimeter Array (ALMA) have revolutionized our understanding of protoplanetary disks chemical composition and physical properties, revealing in some cases complex radial, vertical, and azimuthal structure in the dust and gas. In this contribution, I review recent observational results and new theoretical puzzles, and how these fit into a newly emerging picture of the disk environment.

The diverse chemistry of protoplanetary disks as revealed by JWST

“…GW Lup is part of a handful of sources that were found by Spitzer to have strong CO 2 emission but no emission from other molecules, the so-called "CO 2only" sources. 10 Thanks to the detection of 12 CO 2 hot bands, its P-and R-branch lines and the 13 CO 2 Q-branch, the inferred CO 2 column density is two orders of magnitude higher (and emitting area smaller) than found in analyses of the Spitzer data, illustrating the importance of the additional weaker optically thin features now observed with MIRI-MRS. 31 H 2 O and other molecules are now weakly detected as well with JWST, but its CO 2 /H 2 O column density ratio remains clearly higher than that of other low-mass sources.…”

“…The blue tickmarks in the V1094 Sco, Sz 98 and GW Lup panels indicate the locations of water lines. Note also the detected 13 CO 2 and hot bands of12 CO 2 toward GW Lup 31. The bottom panel shows the simulated LTE slab model spectra of CO 2 and H 2 O at 600 K (arbitrary relative scaling).…”