Chaston C C, Wilber M, Mozer F S, Fujimoto M, Goldstein M L, Acuna M, Reme H, Fazakerley A
Space Science Laboratory, University of California, Berkeley, California, USA.
Phys Rev Lett. 2007 Oct 26;99(17):175004. doi: 10.1103/PhysRevLett.99.175004.
Observations at the Earth's magnetopause identify mode conversion from surface to kinetic Alfvén waves at the Alfvén resonance. Kinetic Alfvén waves radiate into the magnetosphere from the resonance with parallel scales up to the order of the geomagnetic field-line length and spectral energy densities obeying a k(perpendicular)(-2.4) power law. Amplitudes at the Alfvén resonance are sufficient to both demagnetize ions across the magnetopause and provide field-aligned electron bursts. These waves provide diffusive transport across the magnetopause sufficient for boundary layer formation.
在地球磁层顶的观测发现,在阿尔文共振处存在从表面波到动力学阿尔文波的模式转换。动力学阿尔文波从共振处辐射到磁层中,其平行尺度可达地磁场线长度的量级,且谱能量密度遵循k(垂直)(-2.4)幂律。阿尔文共振处的振幅足以使磁层顶两侧的离子退磁,并产生场向电子爆发。这些波提供了足以形成边界层的跨磁层顶扩散输运。