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arXiv · 1604.05670

Spatial Distribution of Pair Production over the Pulsar Polar Cap

Mikhail A. Belyaev·Kyle Parfrey
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Abstract

Using an analytic, axisymmetric approach that includes general relativity, coupled to a condition for pair production deduced from simulations, we derive general results about the spatial distribution of pair-producing field lines over the pulsar polar cap. In particular, we show that pair production on magnetic field lines operates over only a fraction of the polar cap for an aligned rotator for general magnetic field configurations, assuming the magnetic field varies spatially on a scale that is larger than the size of the polar cap. We compare our result to force-free simulations of a pulsar with a dipole surface field and find excellent agreement. Our work has implications for first-principles simulations of pulsar magnetospheres, and for explaining observations of pulsed radio and high-energy emission.

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Mikhail A. Belyaev, Kyle Parfrey. 2016-07-12. Spatial Distribution of Pair Production over the Pulsar Polar Cap. https://doi.org/10.3847/0004-637x%2F830%2F2%2F119

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