...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research, A. Space Physics: JGR >Generation of magnetosonic waves over a continuous spectrum
【24h】

Generation of magnetosonic waves over a continuous spectrum

机译：代magnetosonic波在一个连续的光谱

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Magnetosonic waves, also known as equatorial noise emission, were found to have discrete frequency structures, which is consistent with instability caused by proton ring distribution. Nonetheless, nondiscrete structure, i.e., a broadband spectrum over a continuous frequency range, has been reported. We investigate the question whether proton ring distribution can generate nondiscrete spectra for perpendicularly propagating magnetosonic waves. We propose discrete and nondiscrete characteristics of the local instability for explaining the observation of discrete, continuous, and mixed spectra. The criterion for transition from discrete and continuous instability is given, γ > ～ Ω_h∕2, where γ is wave growth rate and Ω_h is proton cyclotron frequency. The condition is verified by particle-in-cell simulation using more realistic electron-to-proton mass ratio and speed of light than in previous studies. Such criterion of generating a continuous spectrum can be tested against simultaneous in situ measurement of wave and particle. We also find that the modes at low Ω_h harmonics, including the fundamental Ω_h, can be still excited through nonlinear wave-wave coupling, even when they are neutral modes (γ = 0) according to the linear kinetic theory. Comparison with magnetosonic waves in cold plasma limit and electromagnetic ion Bernstein mode is also discussed.
机译：Magnetosonic电波,也被称为赤道噪音发射,发现离散频率结构,这是一致的不稳定由于质子环形分布。非离散结构,即宽带频谱在一个连续的频率范围,报道。质子环可以生成非离散分布光谱的垂直地传播magnetosonic波。当地的非离散特征不稳定来解释的观测离散、连续和混合光谱。从离散和标准转变持续不稳定,γ> ~Ω_h∕2,在γ波增长率和Ω_h质子吗回旋频率。particle-in-cell模拟使用更为现实electron-to-proton质量比和速度的光比先前的研究。生成一个连续谱可以进行测试对同步原位测量的波和粒子。Ω_h谐波,包括基本Ω_h,可以通过非线性波波还是兴奋耦合,即使他们是中性的模式(γ=根据线性分子运动论0)。在冷等离子体与magnetosonic波限制和电磁离子伯恩斯坦模式还讨论了。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号