Abstract

Massive stars play an essential role in the Universe. They are rare, yet the energy and momentum they inject into the interstellar medium (ISM) with their intense radiation fields dwarfs the contribution by their vastly more numerous low-mass cousins. Massive stars form in magnetized, dense, and cold molecular gas from the gravitational collapse of massive pre-stellar cores located in highly embedded environments. During their formation, feedback from their intense radiation fields, magnetically launched collimated protostellar outflows, and fast, isotropic radiatively driven winds can limit their growth by accretion. In this talk, I will show a series of radiation- magnetohydrodynamic (RMHD) simulations of the collapse of massive pre-stellar cores into massive stellar systems that include these feedback processes to demonstrate how stellar feedback can limit accretion onto massive stars. Furthermore, I will also discuss how stellar feedback from massive stars, which are born in clustered environments, affects the dynamics of HII regions that surround these clusters and can drive ISM turbulence in young, star clusters.