Interaction of the central jet with the surrounding gas in the protostellar outflow from IRAS 04166+2706

Vol. 706
6. Interstellar and circumstellar matter

Interaction of the central jet with the surrounding gas in the protostellar outflow from IRAS 04166+2706

How protostellar jets structure and interact with their surroundings is a major challenge for understanding feedback in the star formation process. This study provides an exquisite multimolecular-tracer view of the dynamics in the bipolar outflow of a Class 0 protostar. The jets show two distinct components, distinguished by their velocity intervals: one, below about 25 km/s with a conical, wall-bounded structure, and the other at higher velocities with distinct quasiperiodic arcs and shocks in the inner core indicating a shearing flow within the outer walls. The authors present and model a remarkable set of ALMA CO (2-1) observations, reproducing with pulsed shearing ejections the velocity-position characteristics of both jets. The paper is a harbinger of things to come as more protostellar sources are studied with high-spatial and velocity resolution, showing the wealth of energetic and dynamical information that can be retrieved from spectral line observations.