Magnetic Field Amplification by Turbulence in A Relativistic Shock Propagating through An Inhomogeneous Medium

Дата и время публикации : 2010-11-08T14:38:04Z

Авторы публикации и институты :
Yosuke Mizuno
Martin Pohl
Jacek Niemiec
Bing Zhang
Ken-Ichi Nishikawa
Philip E. Hardee

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 22 pages, 9 figures, accepted for publication in ApJ
Первичная категория: astro-ph.HE

Все категории : astro-ph.HE

Краткий обзор статьи: We perform two-dimensional relativistic magnetohydrodynamic simulations of a mildly relativistic shock propagating through an inhomogeneous medium. We show that the postshock region becomes turbulent owing to preshock density inhomogeneity, and the magnetic field is strongly amplified due to the stretching and folding of field lines in the turbulent velocity field. The amplified magnetic field evolves into a filamentary structure in two-dimensional simulations. The magnetic energy spectrum is flatter than the Kolmogorov spectrum and indicates that a so-called small-scale dynamo is occurring in the postshock region. We also find that the amount of magnetic-field amplification depends on the direction of the mean preshock magnetic field, and the time scale of magnetic-field growth depends on the shock strength.

Category: Physics