ALMA and VLA observations of the outflows in IRAS 16293-2422

TL;DR

This study uses ALMA and VLA observations to analyze the outflows in IRAS 16293-2422, revealing episodic jets, the origins of large-scale flows, and identifying the youngest protostar in the system.

Contribution

It provides high-resolution imaging that clarifies the origins and characteristics of multiple outflows in IRAS 16293-2422, including the first detection of a bubble-like outflow from source B.

Findings

Source A2 drives a large-scale NE-SW outflow.

Source A exhibits episodic jet activity.

A new bubble-like outflow from source B is detected.

Abstract

We present ALMA and VLA observations of the molecular and ionized gas at 0.1-0.3 arcsec resolution in the Class 0 protostellar system IRAS 16293-2422. These data clarify the origins of the protostellar outflows from the deeply embedded sources in this complex region. Source A2 is confirmed to be at the origin of the well known large scale north-east--south-west flow. The most recent VLA observations reveal a new ejection from that protostar, demonstrating that it drives an episodic jet. The central compact part of the other known large scale flow in the system, oriented roughly east-west, is well delineated by the CO(6-5) emission imaged with ALMA and is confirmed to be driven from within component A. Finally, a one-sided blueshifted bubble-like outflow structure is detected here for the first time from source B to the north-west of the system. Its very short dynamical timescale (~ 200 yr), low velocity, and moderate collimation support the idea that source B is the youngest object in the system, and possibly one of the youngest protostars known.