A new algorithm for radiative feedback and its application to the formation of massive stars

We have developed a simplified method of treating the radiative acceleration of dusty flows. This method retains the sharp impulse at the dust destruction radius that is a feature of frequency-dependent radiative transfer, whilst placing minimal demands on computing resources. As such, it is suitable for inclusion in hydrodynamic codes. We have applied this method to the formation of massive stars in spherical geometry, and find that the fraction of a cloud that can accrete on to the central star is a strong function of the Jeans number and density profile of the cloud. Massive star formation is favoured by cold homogeneous conditions, as might result in regions where the gas is swept up by some external triggering agent. We find (in contrast to previous authors) that massive star formation does not require a depleted dust mixture, although the use of dust at typical interstellar abundances does reduce the final stellar mass compared with cores formed from a depleted mixture.