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Title: ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE

Abstract

In this paper, we report on turbulent acceleration of the dissipation of the magnetic field in the post-shock region of a Poynting flux-dominated flow, such as the Crab pulsar wind nebula. We have performed two-dimensional resistive relativistic magnetohydrodynamics simulations of subsonic turbulence driven by the Richtmyer-Meshkov instability at the shock fronts of the Poynting flux-dominated flows in pulsar winds. We find that turbulence stretches current sheets which substantially enhances the dissipation of the magnetic field, and that most of the initial magnetic field energy is dissipated within a few eddy-turnover times. We also develop a simple analytical model for turbulent dissipation of the magnetic field that agrees well with our simulations. The analytical model indicates that the dissipation rate does not depend on resistivity even in the small resistivity limit. Our findings can possibly alleviate the {sigma}-problem in the Crab pulsar wind nebulae.

Authors:
 [1];  [2];  [3]
  1. Department of Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan)
  2. Department of Physics and Mathematics, Aoyama Gakuin University, Fuchinobe, Chuou-ku, Sagamihara 252-5258 (Japan)
  3. Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)
Publication Date:
OSTI Identifier:
22039117
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 755; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; ASTRONOMY; ASTROPHYSICS; COMPUTERIZED SIMULATION; CRAB NEBULA; ELECTRIC CURRENTS; INSTABILITY; INTERSTELLAR MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; PLASMA; PULSARS; RELATIVISTIC RANGE; SHOCK WAVES; STELLAR WINDS; TURBULENCE; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Takamoto, Makoto, Inoue, Tsuyoshi, and Inutsuka, Shu-ichiro, E-mail: takamoto@tap.scphys.kyoto-u.ac.jp, E-mail: inouety@phys.aoyama.ac.jp, E-mail: inutsuka@nagoya-u.jp. ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE. United States: N. p., 2012. Web. doi:10.1088/0004-637X/755/1/76.
Takamoto, Makoto, Inoue, Tsuyoshi, & Inutsuka, Shu-ichiro, E-mail: takamoto@tap.scphys.kyoto-u.ac.jp, E-mail: inouety@phys.aoyama.ac.jp, E-mail: inutsuka@nagoya-u.jp. ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE. United States. doi:10.1088/0004-637X/755/1/76.
Takamoto, Makoto, Inoue, Tsuyoshi, and Inutsuka, Shu-ichiro, E-mail: takamoto@tap.scphys.kyoto-u.ac.jp, E-mail: inouety@phys.aoyama.ac.jp, E-mail: inutsuka@nagoya-u.jp. 2012. "ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE". United States. doi:10.1088/0004-637X/755/1/76.
@article{osti_22039117,
title = {ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE},
author = {Takamoto, Makoto and Inoue, Tsuyoshi and Inutsuka, Shu-ichiro, E-mail: takamoto@tap.scphys.kyoto-u.ac.jp, E-mail: inouety@phys.aoyama.ac.jp, E-mail: inutsuka@nagoya-u.jp},
abstractNote = {In this paper, we report on turbulent acceleration of the dissipation of the magnetic field in the post-shock region of a Poynting flux-dominated flow, such as the Crab pulsar wind nebula. We have performed two-dimensional resistive relativistic magnetohydrodynamics simulations of subsonic turbulence driven by the Richtmyer-Meshkov instability at the shock fronts of the Poynting flux-dominated flows in pulsar winds. We find that turbulence stretches current sheets which substantially enhances the dissipation of the magnetic field, and that most of the initial magnetic field energy is dissipated within a few eddy-turnover times. We also develop a simple analytical model for turbulent dissipation of the magnetic field that agrees well with our simulations. The analytical model indicates that the dissipation rate does not depend on resistivity even in the small resistivity limit. Our findings can possibly alleviate the {sigma}-problem in the Crab pulsar wind nebulae.},
doi = {10.1088/0004-637X/755/1/76},
journal = {Astrophysical Journal},
number = 1,
volume = 755,
place = {United States},
year = 2012,
month = 8
}
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