The roles of stellar feedback and galactic environment in star-forming molecular clouds
Monthly Notices of the Royal Astronomical Society
Oxford University Press (OUP)
© 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
Feedback from massive stars is thought to play an important role in the evolution of molecular clouds. In this work we analyse the effects of stellar winds and supernovae (SNe) in the evolution of two massive (∼ 106 M ) giant molecular clouds (GMCs): one gravitationally bound collapsing cloud and one unbound cloud undergoing disruption by galactic shear. These two clouds have been extracted from a large scale galaxy model and are re-simulated at a spatial resolution of ∼ 0.01 pc, including feedback from winds, SNe, and the combined effect of both. We find that stellar winds stop accretion of gas onto sink particles, and can also trigger star formation in the shells formed by the winds, although the overall effect is to reduce the global star formation rate of both clouds. Furthermore, we observe that winds tend to escape through the corridors of diffuse gas. The effect of SNe is not so prominent and the star formation rate is similar to models neglecting stellar feedback. We find that most of the energy injected by the SNe is radiated away, but overdense areas are created by multiple and concurrent SN events especially in the most virialised cloud. Our results suggest that the impact of stellar feedback is sensitive to the morphology of star forming clouds, which is set by large scale galactic flows, being of greater importance in clouds undergoing gravitational collapse.
The calculations for this paper were performed on the supercomputer at Exeter, which is jointly funded by STFC, the Large Facilities Capital Fund of BIS and the University of Exeter. RRR and CLD acknowledge funding from the European Research Council for the FP7 ERC starting grant project LOCALSTAR. OA and RRR would like to acknowledge support from STFC consolidated grant ST/M000990/1. Figs 1, 2, 5, and 3 were produced using SPLASH (Price 2007).
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.
Vol. 464, pp. 3536 - 3551