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arXiv · 1012.3663

The Appearance of a Radio-Pulsar Magnetosphere from a Vacuum with a Strong Magnetic Field. Accumulation of Particles

Ya. N. Istomin·D. N. Sob'yanin
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Abstract

The accumulation of electrons and positrons in the vacuum magnetosphere of a neutron star with a surface magnetic field of B~10^12 G is considered. It is shown that particles created in the magnetosphere or falling into the magnetosphere from outside undergo ultra-relativistic oscillations with a frequency of 10-100 MHz. These oscillations decay due to energy losses to curvature radiation and bremsstrahlung, with their frequencies reaching 1-10 GHz. Simultaneously, the particles undergo regular motion along the force-free surface along closed trajectories. This leads to the gradual accumulation of particles at the force-free surface and the formation of a fully charge-separated plasma layer with a density of the order of the Goldreich-Julian density. The presence of a constant source of electron-positron pairs in the magnetosphere due to the absorption of energetic cosmic gamma-rays leads to the growth of this layer, bringing about a rapid filling of the pulsar magnetosphere with electron-positron plasma if the pair-creation multiplication coefficient is sufficiently high.

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Ya. N. Istomin, D. N. Sob'yanin. 2010-12-16. The Appearance of a Radio-Pulsar Magnetosphere from a Vacuum with a Strong Magnetic Field. Accumulation of Particles. https://doi.org/10.1134/s1063772910040074

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