Effects of stellar feedback on cores in STARFORGE

TL;DR

This study uses hierarchical clustering analysis on STARFORGE simulations to examine how stellar feedback mechanisms like outflows, winds, and supernovae influence the properties and evolution of dense cores in molecular clouds.

Contribution

It provides a detailed analysis of the impact of stellar feedback on core properties using a hierarchical clustering approach in a simulated giant molecular cloud.

Findings

Cores affected by more feedback are smaller.

Feedback increases velocity dispersion and virial parameter.

Higher feedback cores show higher velocities in linewidth-size relation.

Abstract

Stars form in dense cores within molecular clouds and newly formed stars influence their natal environments. How stellar feedback impacts core properties and evolution is subject to extensive investigation. We performed a hierarchical clustering (dendrogram) analysis of a STARFORGE simulation modelling a giant molecular cloud to identify gas overdensities (cores) and study changes in their radius, mass, velocity dispersion, and virial parameter with respect to stellar feedback. We binned these cores on the basis of the fraction of gas affected by protostellar outflows, stellar winds, and supernovae and analysed the property distributions for each feedback bin. We find that cores that experience more feedback influence are smaller. Feedback notably enhances the velocity dispersion and virial parameter of the cores, more so than it reduces their radius. This is also evident in the linewidth-size relation, where cores in higher feedback bins exhibit higher velocities than their similarly sized pristine counterparts. We conclude that stellar feedback mechanisms, which impart momentum to the molecular cloud, simultaneously compress and disperse the dense molecular gas.