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		| Paper: | 
		Ab initio simulations of accretion disc boundary layers | 
	 
	
		| Volume: | 
		261, The Physics of Cataclysmic Variables and Related Objects | 
	 
	
		| Page: | 
		425 | 
	 
	
		| Authors: | 
		Armitage, P. J. | 
	 
	
	
		| Abstract: | 
		I discuss the results of simplified three dimensional magnetohydrodynamic simulations of the boundary layer between a disc and a non-rotating, unmagnetized star. Strong magnetic fields, possibly approaching equipartition with the thermal energy, occur in the boundary layer due to the shearing of disc-generated fields. The mean boundary layer magnetic field, which is highly variable on an orbital timescale, is estimated to exceed ~50 kG for a CV with an accretion rate of 10-9 Modot yr-1. However, these fields do not drive efficient angular momentum transport within the boundary layer. As a consequence the radial velocity in the boundary layer is low, and the density high. | 
	 
	
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