Gas flow and accretion via spiral streamers and circumstellar disks in a young binary protostar

TL;DR

This study presents high-resolution observations of a young binary protostar system, revealing complex disk and filament structures, accretion patterns, and jets, providing insights into stellar multiplicity formation.

Contribution

First detailed high-angular resolution imaging of a young binary protostar with analysis of disk, filament, and accretion dynamics.

Findings

Circumstellar disks of 2-3 AU radius around each protostar.

Filamentary structures connecting to the circumbinary disk.

Preferential accretion onto the lower-mass protostar.

Abstract

The majority of stars are part of gravitationally bound stellar systems, such as binaries. Observations of protobinary systems constrain the conditions that lead to stellar multiplicity and subsequent orbital evolution. We report high-angular resolution observations of the circumbinary disk around [BHB2007] 11, a young binary protostar system. The two protostars are embedded in circumstellar disks that have radii of 2 to 3 astronomical units and probably contain a few Jupiter masses. These systems are surrounded by a complex structure of filaments connecting to the larger circumbinary disk. We also observe accretion and radio jets associated with the protobinary system. The accretion is preferentially onto the lower-mass protostar, consistent with theoretical predictions.