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Title: Two-fluid model of the pulsar magnetosphere represented as an axisymmetric force-free dipole

Abstract

Based on the exact dipolar solution of the pulsar equation the self-consistent two-fluid model of the pulsar magnetosphere is developed. We concentrate on the low-mass limit of the model, taking into account the radiation damping. As a result, we obtain the particle distributions sustaining the dipolar force-free configuration of the pulsar magnetosphere in case of a slight velocity shear of the electron and positron components. Over most part of the force-free region, the particles follow the poloidal magnetic field lines, with the azimuthal velocities being small. Close to the Y-point, however, the particle motion is chiefly azimuthal and the Lorentz-factor grows unrestrictedly. This may result in the very-high-energy emission from the vicinity of the Y-point and may also imply the magnetocentrifugal formation of a jet. As for the first-order quantities, the longitudinal accelerating electric field is found to change the sign, hinting at coexistence of the polar and outer gaps. Besides that, the components of the plasma conductivity tensor are derived and the low-mass analogue of the pulsar equation is formulated as well.

Authors:
 [1]
  1. Institute of Radio Astronomy of the NAS of Ukraine, Mystetstv Str., 4, Kharkiv 61002 (Ukraine)
Publication Date:
OSTI Identifier:
22676195
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIAL SYMMETRY; COMPUTERIZED SIMULATION; CONFIGURATION; DIPOLES; DISTRIBUTION; ELECTRIC FIELDS; ELECTRONS; EMISSION; EQUATIONS; FLUIDS; MAGNETIC FIELDS; MASS; PLASMA; POSITRONS; PULSARS; VELOCITY

Citation Formats

Petrova, S.A., E-mail: petrova@rian.kharkov.ua. Two-fluid model of the pulsar magnetosphere represented as an axisymmetric force-free dipole. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/05/041.
Petrova, S.A., E-mail: petrova@rian.kharkov.ua. Two-fluid model of the pulsar magnetosphere represented as an axisymmetric force-free dipole. United States. doi:10.1088/1475-7516/2017/05/041.
Petrova, S.A., E-mail: petrova@rian.kharkov.ua. Mon . "Two-fluid model of the pulsar magnetosphere represented as an axisymmetric force-free dipole". United States. doi:10.1088/1475-7516/2017/05/041.
@article{osti_22676195,
title = {Two-fluid model of the pulsar magnetosphere represented as an axisymmetric force-free dipole},
author = {Petrova, S.A., E-mail: petrova@rian.kharkov.ua},
abstractNote = {Based on the exact dipolar solution of the pulsar equation the self-consistent two-fluid model of the pulsar magnetosphere is developed. We concentrate on the low-mass limit of the model, taking into account the radiation damping. As a result, we obtain the particle distributions sustaining the dipolar force-free configuration of the pulsar magnetosphere in case of a slight velocity shear of the electron and positron components. Over most part of the force-free region, the particles follow the poloidal magnetic field lines, with the azimuthal velocities being small. Close to the Y-point, however, the particle motion is chiefly azimuthal and the Lorentz-factor grows unrestrictedly. This may result in the very-high-energy emission from the vicinity of the Y-point and may also imply the magnetocentrifugal formation of a jet. As for the first-order quantities, the longitudinal accelerating electric field is found to change the sign, hinting at coexistence of the polar and outer gaps. Besides that, the components of the plasma conductivity tensor are derived and the low-mass analogue of the pulsar equation is formulated as well.},
doi = {10.1088/1475-7516/2017/05/041},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2017,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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