TWO-FLUID MODEL OF THE MAGNETOSPHERE AS A BASIS FOR DESCRIPTION OF PULSAR EMISSION

DOI: https://doi.org/10.15407/rpra21.04.249

S. A. Petrova

Abstract


PACS numbers: 97.60.Gb, 97.60.Jd, 95.30.Lz   

Purpose: The self-consistent two-fluid model for the stationary axisymmetric magnetosphere of a pulsar is considered.

Design/methodology/approach: Taking into account infinitesimal inertial effects, the zero- and first-order equations are solved. The general results are applied to the case of a small difference in the distributions of the two particle species in the magnetosphere of a monopolar structure.

Results: The physically grounded distribution functions for the electron and positron constituents of the pulsar plasma are found, which sustain the force-free configuration of the magnetosphere. The approach developed enables us to consistently incorporate emission into the force-free model of the pulsar magnetosphere. Within the framework of our consideration, the plasma conductivity along the poloidal magnetic field appears of the order of the inverse particle mass, in contrast to the finite conductivity of “massless” particles typically assumed in the literature.

Conclusions: The model constructed has important implications not only for the high-energy emission but also for the radio emission of pulsars. In the force-free plasma flow, the two-stream and diocotron instabilities can develop, leading to the radio emission generation and subpulse drift, respectively. Then, the pulsar radio emission appears physically connected to the high-energy emission.

Key words: force-free magnetosphere, two-fluid model, inertial effects, conductivity of pulsar plasma, pulsar radio emission

Manuscript submitted 22.08.2016 г.

Radio phys. radio astron. 2016, 21(4): 249-259 

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Keywords


force-free magnetosphere; two-fluid model; inertial effects; conductivity of pulsar plasma; pulsar radio emission

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