The Molecular Outflows in the rho Ophiuchi Main Cloud: Implications For Turbulence Generation

TL;DR

This study maps molecular outflows in the rho Ophiuchi cloud, revealing their potential role in sustaining turbulence, with the most luminous outflow from VLA 1623 and significant energy contributions from multiple sources.

Contribution

First detailed CO (J=3-2) and (J=1-0) mapping of outflows in rho Ophiuchi, linking outflow activity to turbulence maintenance in the cloud.

Findings

Identified five molecular outflows driven by young stellar objects.

The total outflow energy injection rate exceeds turbulence dissipation rate.

Outflows, especially from VLA 1623 and EL 32, significantly contribute to cloud turbulence.

Abstract

We present the results of CO (J=3-2) and CO (J=1-0) mapping observations toward the active cluster forming clump, L1688, in the rho Ophiuchi molecular cloud. From the CO (J=3-2) and CO (J=1-0) data cubes, we identify five outflows, whose driving sources are VLA 1623, EL 32, LFAM 26, EL 29, and IRS 44. Among the identified outflows, the most luminous outflow is the one from the prototypical Class 0 source, VLA 1623. We also discover that the EL 32 outflow located in the Oph B2 region has very extended blueshifted and redshifted lobes with wide opening angles. This outflow is most massive and have the largest momentum among the identified outflows in the CO (J=1-0) map. We estimate the total energy injection rate due to the molecular outflows identified by the present and previous studies to be about 0.2 L_solar, larger than or at least comparable to the turbulence dissipation rate [~(0.03 - 0.1) L_solar]. Therefore, we conclude that the protostellar outflows are likely to play a significant role in replenishing the supersonic turbulence in this clump.