Speaker
Mr
Benjamin Lewis
(University of Exeter)
Description
We expand on Lewis, et al. (2015) and (2016, submitted), which considered only ideal MHD simulations of the collapse of molecular cloud cores without turbulence, and use radiation magnetohydrodynamical calculations to explore how the physics of turbulence, rotation, magnetism and radiation influences the formation of protostars.
The inclusion of a flux limited diffusion radiative transfer (FLD R-T) scheme in the SPH calculations (i.e. an SPRMHD scheme) promotes the formation of larger discs, as opposed to the very small and dense discs produced by the MHD only calculations. We also find that the gravitational collapse proceeds in a very different manner in cores with transonic turbulence compared with subsonic cores across a wide variety of field strengths and geometries. Cores with subsonic - and in particular very subsonic - turbulence still contain a bipolar jet and (depending on the magnetic field) form a pseudo-disc, albeit without the symmetry seen for laminar cores. Transonic (i.e. ~ Mach 1) cores are highly disrupted by the turbulent motion, which acts to suppress the formation of a pseudo-disc and hence a bipolar outflow. However, increasing the initial angular momentum of the core so that the rotational and turbulent energies are approximately equal allows even turbulent cores to produce jets and outflows.
Author
Mr
Benjamin Lewis
(University of Exeter)
Co-author
Prof.
Matthew Bate
(University of Exeter)
