Talks & Events

Ph.D. Thesis Defenses: 1996
Turbulent Diffusion of LargeScale Magnetic Fields in the Presence of Ambipolar Drift EunJin Kim The decay of a largescale magnetic field embedded in a weaklyionized fluid is studied in twodimensional geometry. We consider cases where the magnetic energy density is less than the total kinetic energy density. Using both quasilinear analysis and numerical simulations, we show that when the motions of the neutrals are turbulent, the effective diffusivity of a largescale magnetic field depends on both the magnetic field strength and the frictional coupling constant between ions and neutrals. The effective diffusivity is comparable to the turbulent rate if the magnetic field is weak enough and if the frictional coupling is strong enough. However, for values of the parameters typical of the interstellar medium, we show that turbulent diffusion is bound to be reduced. 