The JCMT Gould Belt Survey: Understanding the influence of molecular outflows on Gould Belt clouds

TL;DR

This study analyzes molecular outflows in Gould Belt star-forming regions, revealing their significant energy contribution but limited role in driving turbulence, suggesting other mechanisms are primarily responsible for turbulence.

Contribution

It provides a comprehensive meta-analysis of outflows and their energetics across multiple Gould Belt clouds using JCMT data, highlighting their limited impact on turbulence.

Findings

Outflows transport large momentum and energy.

Outflow energies are at least 20% of turbulent kinetic energies.

Outflows do not significantly increase turbulence levels.

Abstract

Using JCMT Gould Belt Survey data from CO J=3-2 isotopologues, we present a meta-analysis of the outflows and energetics of star-forming regions in several Gould Belt clouds. The majority of the regions are strongly gravitationally bound. There is evidence that molecular outflows transport large quantities of momentum and energy. Outflow energies are at least 20 per cent of the total turbulent kinetic energies in all of the regions studied and greater than the turbulent energy in half of the regions. However, we find no evidence that outflows increase levels of turbulence, and there is no correlation between the outflow and turbulent energies. Even though outflows in some regions contribute significantly to maintaining turbulence levels against dissipation, this relies on outflows efficiently coupling to bulk motions. Other mechanisms (e.g. supernovae) must be the main drivers of turbulence in most if not all of these regions.