A Massive Star is Born: How Feedback from Stellar Winds, Radiation
  Pressure, and Collimated Outflows Limits Accretion onto Massive Stars
  Massive protostars attain high luminosities as they are actively accreting
and the radiation pressure exerted on the gas in the star's atmosphere may
launch isotropic high-velocity ($v_{\rm w} \gtrsim 10^3$ km/s) winds. These
winds will collide with the surrounding gas producing shock-heated ($T\sim
10^7$ K) tenuous gas that adiabatically expands and pushes on the dense gas
that may otherwise be accreted. We present a series of 3D
radiation-magnetohydrodynamic simulations of the collapse of massive prestellar
cores and include radiative feedback from the direct stellar and
dust-reprocessed radiation fields, collimated outflows, and, for the first
time, isotropic stellar winds to model how these processes affect the formation
of massive (proto)stars. We find that winds are initially launched when the
massive protostar is still accreting and the wind properties evolve as the star
contracts to the main sequence. Wind feedback drives asymmetric adiabatic wind
bubbles that have a bipolar morphology because the dense circumstellar material
pinches the expansion of the hot shock-heated gas, which preferentially expands
along low-density channels. We term this the "wind tunnel effect." For
unmagnetized cores, we find that wind feedback eventually quenches accretion
onto massive stars. For magnetized cores, we find that wind feedback is less
efficient at halting the accretion flow initially because magnetic tension
delays the growth of the wind-driven bubbles. Once winds become strong enough,
wind feedback launches adiabatic wind bubbles that eventually reduce accretion.
Additionally, we discuss the implications of observing adiabatic wind bubbles
with Chandra while the massive protostars are still highly embedded.
