Magnetic Helicity Conservation and Inverse Energy Cascade in Electron Magnetohydrodynamic Wave Packets

Journal Article · Fri May 13 00:00:00 EDT 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.106.191104· OSTI ID:21538321

Cho, Jungyeon ^[1]

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1. Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of)

Electron magnetohydrodynamics (EMHD) provides a fluidlike description of small-scale magnetized plasmas. An EMHD wave propagates along magnetic field lines. The direction of propagation can be either parallel or antiparallel to the magnetic field lines. We numerically study propagation of three-dimensional (3D) EMHD wave packets moving in one direction. We obtain two major results. (1) Unlike its magnetohydrodynamic (MHD) counterpart, an EMHD wave packet is dispersive. Because of this, EMHD wave packets traveling in one direction create opposite-traveling wave packets via self-interaction and cascade energy to smaller scales. (2) EMHD wave packets traveling in one direction clearly exhibit inverse energy cascade. We find that the latter is due to conservation of magnetic helicity. We compare inverse energy cascade in 3D EMHD turbulence and two-dimensional (2D) hydrodynamic turbulence.

• OSTI ID: 21538321
• Journal Information: Physical Review Letters, Vol. 106, Issue 19; Other Information: DOI: 10.1103/PhysRevLett.106.191104; (c) 2011 American Institute of Physics; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ELECTRONS
HELICITY
HYDROMAGNETIC WAVES
INTERACTIONS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
PLASMA
THREE-DIMENSIONAL CALCULATIONS
TRAVELLING WAVES
TURBULENCE
TWO-DIMENSIONAL CALCULATIONS
WASTE HEAT UTILIZATION
WAVE PACKETS
ELEMENTARY PARTICLES
FERMIONS
FLUID MECHANICS
HYDRODYNAMICS
LEPTONS
MECHANICS
PARTICLE PROPERTIES
WASTE PRODUCT UTILIZATION