skip to main content

SciTech ConnectSciTech Connect

Title: Comparison of formulas for resonant interactions between energetic electrons and oblique whistler-mode waves

Test particle simulation is a useful method for studying both linear and nonlinear wave-particle interactions in the magnetosphere. The gyro-averaged equations of particle motion for first-order and other cyclotron harmonic resonances with oblique whistler-mode waves were first derived by Bell [J. Geophys. Res. 89, 905 (1984)] and the most recent relativistic form was given by Ginet and Albert [Phys. Fluids B 3, 2994 (1991)], and Bortnik [Ph.D. thesis (Stanford University, 2004), p. 40]. However, recently we found there was a (āˆ’1){sup lāˆ’1} term difference between their formulas of perpendicular motion for the lth-order resonance. This article presents the detailed derivation process of the generalized resonance formulas, and suggests a check of the signs for self-consistency, which is independent of the choice of conventions, that is, the energy variation equation resulting from the momentum equations should not contain any wave magnetic components, simply because the magnetic field does not contribute to changes of particle energy. In addition, we show that the wave centripetal force, which was considered small and was neglect in previous studies of nonlinear interactions, has a profound time derivative and can significantly enhance electron phase trapping especially in high frequency waves. This force can also bounce the lowmore » pitch angle particles out of the loss cone. We justify both the sign problem and the missing wave centripetal force by demonstrating wave-particle interaction examples, and comparing the gyro-averaged particle motion to the full particle motion under the Lorentz force.« less
Authors:
 [1] ;  [2] ; ;  [3] ; ; ; ;  [1] ;  [4] ;  [5] ;  [6] ;  [7]
  1. Institute of Space Physics and Applied Technology, Peking University, Beijing 100871 (China)
  2. (United States)
  3. Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, California 90095 (United States)
  4. W. B. Hanson Center for Space Sciences, Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)
  5. Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan, Hubei 430072 (China)
  6. Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China)
  7. Mullard Space Science Laboratory, University College London, Dorking (United Kingdom)
Publication Date:
OSTI Identifier:
22410328
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CYCLOTRON RESONANCE; EARTH MAGNETOSPHERE; INCLINATION; LORENTZ FORCE; LOSS CONE; MAGNETIC FIELDS; PARTICLE INTERACTIONS; RELATIVISTIC RANGE; SIMULATION; TAIL ELECTRONS; TEST PARTICLES; TRAPPED ELECTRONS; WHISTLER INSTABILITY