ELECTRON ACCELERATION AT A LOW MACH NUMBER PERPENDICULAR COLLISIONLESS SHOCK

Journal Article · Fri Apr 10 04:00:00 EDT 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/695/1/574; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21296263

Umeda, Takayuki; Yamao, Masahiro ^[1]; Yamazaki, Ryo ^[2]

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1. Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601 (Japan)
2. Department of Physical Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan)

A full particle simulation study is carried out on the electron acceleration at a collisionless, relatively low Alfven Mach number (M{sub A} = 5), perpendicular shock. Recent self-consistent hybrid shock simulations have demonstrated that the shock front of perpendicular shocks has a dynamic rippled character along the shock surface of low Mach number perpendicular shocks. In this paper, the effect of the rippling of perpendicular shocks on the electron acceleration is examined by means of large-scale (ion-scale) two-dimensional full particle simulations. It has been shown that a large-amplitude electric field is excited at the shock front in association with the ion-scale rippling, and that reflected ions are accelerated upstream at a localized region where the shock-normal electric field of the rippled structure is polarized upstream. The current-driven instability caused by the highly accelerated reflected ions has a high growth rate of up to large-amplitude electrostatic waves. Energetic electrons are then generated by the large-amplitude electrostatic waves via electron surfing acceleration at the leading edge of the shock-transition region. The present result suggests that the electron surfing acceleration is also a common feature at low Mach number perpendicular collisionless shocks.

• OSTI ID: 21296263
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 695; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
ACCELERATION
ELECTRIC FIELDS
MACH NUMBER
PLASMA WAVES
SHOCK WAVES
SIMULATION
TAIL ELECTRONS
TWO-DIMENSIONAL CALCULATIONS