Kinematics of Protostellar Objects in the $\rho$ Ophiuchus A Region

Abstract

We present the detection of infall, rotation and outflow kinematic signatures towards both a protostellar source, VLA 1623 and what was initially thought to be a pre-protostellar core, SM1N, in the rho-Ophiuchus A region. The kinematic signatures of early star formation were detected in the dense molecular gas surrounding the embedded sources using high signal-to-noise millimeter and submillimeter data. Centroid velocity maps made with HCO+ J=4->3 and J=1->0 line emission exhibit the blue bulge signature of infall, which is predicted to be seen when infall motion dominates over rotational motion. Further evidence for infalling gas is found in the HCO+ blue asymmetric line profiles and red asymmetric opacity profiles. We also performed CO J=3->2 and J=1->0 observations to determine the direction, orientation, and extent of molecular outflows, and report the discovery of a new bipolar outflow possibly driven by SM1N.