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arXiv · astro-ph/0612682

Relativistic MHD Winds from Rotating Neutron Stars

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Abstract

We solve the time-dependent dynamics of axisymmetric, general relativistic MHD winds from rotating neutron stars. The mass loss rate is obtained self consistently as a solution of the MHD equations, subject to a finite thermal pressure at the stellar surface. Conditions are chosen to be representative of the neutrino driven phase in newly born magnetars, which have been considered as a possible engine for GRBs. We compute the angular momentum and energy losses as a function of $σ$ and compare them with the analytic expectation from the classical theory of pulsar winds. We observe the convergence to the force-free limit in the energy loss and we study the evolution of the closed zone for increasing magnetization. Results also show that the dipolar magnetic field and the presence of a closed zone do not modify significantly the acceleration and collimation properties of the wind.

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N. Bucciantini, T. A. Thompson, J. Arons, E. Quataert. 2006-12-22. Relativistic MHD Winds from Rotating Neutron Stars. https://doi.org/10.1016/j.asr.2007.01.028

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