Oral Presentation
Non-ideal magnetic fields in protostar formation
Presenter: James Wurster (University of Exeter)
Magnetic fields are undeniably a critical factor in star formation. In initially smooth velocity flows, the initial strength of the magnetic field directly affects the mass of the protostar and the characteristics of its disc and outflows. Strong, ideal magnetic fields tend to inhibit disc formation and promote strong, collimated outflows, while large discs and weak outflows form in systems with initially weak magnetic fields. The formation and evolution of the protostar and its environment is considerably modified when a proper treatment of non-ideal magnetohydrodynamics (MHD) is included. Once formed, the protostar itself is highly ionised, however the surrounding gas is still only partially ionised, and the ionisation fraction in the surrounding medium directly influences the evolution of the protostar and environment, despite the high ionisation rate of the protostar itself.
In this talk, I will discuss the effect that non-ideal MHD has on star formation in initially smooth velocity flows. I will focus on the properties of the protostar, discs and outflows, and how these properties vary given different initial magnetic field strengths and ionisation rates.
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