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arXiv · 1003.1275

Observation of the growth of a magnetic vortex in the transition layer of a mildly relativistic oblique plasma shock

G. C. Murphy·M. E. Dieckmann·L. O'C. Drury
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Abstract

A 2D particle simulation models the collision of two electron-ion plasma clouds along a quasi-parallel magnetic field. The collision speed is 0.9c and the density ratio 10. A current sheet forms at the front of the dense cloud, in which the electrons and the magnetic field reach energy equipartition with the ions. A structure composed of a solenoidal and a toroidal magnetic field grows in this sheet. It resembles that in the cross-section of the torus of a force-free spheromak, which may provide the coherent magnetic fields in gamma-ray burst (GRB) jets needed for their prompt emissions.

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G. C. Murphy, M. E. Dieckmann, L. O'C. Drury. 2010-03-05. Observation of the growth of a magnetic vortex in the transition layer of a mildly relativistic oblique plasma shock. https://doi.org/10.1063/1.3493627

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