The Chemical Diversity of Giant-planet Nurseries as Revealed by ALMA

Abstract With the giant exoplanet occurrence rate peaking around stars of 1.5–2.0 solar masses ( M ⊙ ), there is strong motivation to characterize the disks that set their formation conditions. Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) allow us to investigate both the availability of different molecules in disks and infer the radial distribution of elemental abundances, enabling us to make connections to exoplanet systems. Here we present a survey of six transition disks around young F-, A-, and B-type stars using ALMA. We find 13 C 18 O, CS, SO, and H 2 CO in all six systems, as well as 10 additional molecules in a subset of disks, including detections of H 2 S, 33 SO, and CH 3…