Abstract

Until recently, numerical simulations of low-mass star formation have been unable to produce large discs around a forming protostar. This contradicts observations. With the inclusion of non-ideal magnetohydrodynamics (MHD), large discs are now being formed in numerical simulations, indicating the necessity of non-ideal MHD . However, the outcome is somewhat dependent on initial conditions and free parameters, indicating the necessity of carefully choosing realistic parameters. Finally, if the inclusion of non-ideal MHD can self-consistently re-introduce discs, how else does it affect the evolution of the disc? Moreover, what effect will it have on the formation of the protostar itself and the early evolution of its environment?

In this talk, I will first introduce the history and importance of star formation and non-ideal MHD . I will then present the results from our numerical smoothed particle hydrodynamics (SPH) simulations of protostar formation, focusing on the effect that non-ideal MHD has on the formation and early evolution of discs; I will also comment on outflows, magnetic walls and on the evolution of the first and second hydrostatic cores themselves. This will be followed by a discussion on star & disc formation in low-mass clusters, where I will show the importance of modelling stars in a more realistic environment.