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		| Paper: | 
		Magnetospheric Structure and Non-Thermal Emission of AXPs and SGRs | 
	 
	
		| Volume: | 
		271, Neutron Stars in Supernova Remnants | 
	 
	
		| Page: | 
		262 | 
	 
	
		| Authors: | 
		Lyutikov, M.; Thompson, C.; Kulkarni, S. R. | 
	 
	
	
		| Abstract: | 
		In the framework of the magnetar model for the Soft Gamma Repeaters and Anomalous X-ray Pulsars, we consider the structure of neutron star magnetospheres threaded by large-scale electrical currents. We construct self-similar, force-free equilibria under the assumption of axisymmetry and a power law dependence of magnetic field on radius, B ∝ r-(2+p). A large-scale twist of the field lines softens the radial dependence to p < 1, thereby accelerating the spindown torque with respect to a vacuum dipole. A magnetosphere with a strong twist (Bphi/Btheta = O(1) at the equator) has an optical depth ~1 to resonant cyclotron scattering, independent of frequency (radius), surface magnetic field strength, or the charge/mass ratio of the scattering charge. We investigate the effects of the resonant Compton scattering by the charge carriers (both electrons and ions) on the emergent X-ray spectra and pulse profiles. | 
	 
	
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