Protostellar Feedback in Massive Star Forming Regions

Abstract

We examine mechanical feedback mechanisms during the protostellar phase through jets and outflows. To do so, we make use of velocity-resolved CII observations at 158 $\mu$m taken with the SOFIA observatory. We identify CII emitting cavities at velocities ranging from 1-2 km s$^{-1}$ to 15 km s$^{-1}$ relative to the Veil shell ($v_\mathrm{LSR}$ = 13 km s$^{-1}$). The momentum and dynamical timescales of these cavities imply that the cavities in Orion were formed by fossil and active outflows from stars with luminosities ranging from 10$^3$ to 10$^5$ L$_\odot$. The momentum deposited during protostellar feedback is $\sim$1/6 of the momentum of the Veil shell deposited through winds from $\theta^1$ Ori C. By creating cavities, the fossil outflows may already have broken the Veil shell, and outflows from less massive stars may have made the Veil shell porous