Trends of planet formation through chemical analysis of protoplanetary disks

Our solar system’s formation, as well as the formation of exoplanetary systems, may be able to be better explained by studying young stars with disks within young (1-5 Myr) star forming regions, such as Lupus, Rho Ophiucus, and Chameleon 1. Data of 13CO, C18O, C2H, and N2H+ were taken using the Atacama Large Millimeter Array (ALMA) at radio wavelengths, where the detection statistics among the twenty disks for each region was analyzed in relationship with various factors including the disk radial size, the effective temperature of their star, as well as the spatial distribution within a star forming region. Within this, extended disks were more likely to have detections of molecular emission than disks that solely had stars with effective temperatures above K7, while disks that were both extended and had stars hotter than K7 had the most positively identified species. Subregions in Lupus, Rho Ophiuchus, and Chameleon 1 with a higher disk density also generally had more chemical detections attributed to those disks. Separate trends in chemical detections appeared for Lupus and Chameleon 1, and Rho Ophiucus respectively. Lupus and Chameleon one both had appreciable amounts of N2H+ and C2H, suggesting that both CO freeze out had occurred and that there were other hydrocarbon particles, where this abundance of particles suggest that the disks of both of these regions are past the initial stages of planetary formation. Rho Ophiucus, however, lacks N2H+ data, and almost every single disk has 13CO and C18O present within them, with little C2H, suggesting that the disks of this region are still in initial stages of planetary formation.