Yao-Lun Yang (University of Virginia)
Planet formation may start during the embedded phase of star formation. In this scenario, the chemistry of embedded disks may directly determine the chemical composition of the forming planets. In recent years, observations discover several embedded protostars that have developed complex chemistry at the disk-forming region. However, only a few observations attempt to constrain the occurrence of complex molecules at embedded protostars and their relationships to star formation processes. I will present the first result of the Perseus ALMA Chemistry Survey (PEACHES), which aims to unbiasedly survey the chemistry toward 47 embedded protostars with a spatial resolution comparable to the size of disk-forming region. In PEACHES, we identify a variety of molecules and their isotopologues, including CCH, c-C3H2, SO, SO2, CH3OH, CH3CN, CH3OCHO, CH3OCH3, and C2H5OH. For the protostars with emission of complex organic molecules, we find their column densities of complex organic molecules correlate well between species, hinting a similar chemistry for Perseus protostars. Protostellar properties, such as bolometric luminosity and bolometric temperature, have little impact on the occurrence of complex organic molecules. I will also discuss the comparison with the chemistry of the protostars at other regions and environments. The occurrence rate of different complex molecules learned from the PEACHES survey will provide a primer for constraining chemical evolution during the star formation.