Chia-Lin Ko(NTNU); Shih-Ping Lai(NTHU)
Understanding the formation processes of rotationally supported disks around young low-mass protostars is crucial for star formation. In this study, we have observed the Class 0 protostar VLA1623A with the Atacama Millimeter/submillimeter Array (ALMA) in the emission of C18O (J = 2–1) and continuum during the Cycle 2 period. C18O emission shows a velocity gradient perpendicular to the outflow direction and traces a Keplerian rotation in the position-velocity (PV) diagram analysis. To compare with the observations, we use PV diagrams and the thin disk model with the addition of foreground absorption. We reproduce the results with ALMA Cycle 2 data and compare the model presented in the previous work (Murillo et al. 2013) of the ALMA Early Science Cycle 0 observations. We conduct the foreground analysis and find out less foreground components are needed to reproduce the spectrum.