Chorus acceleration of radiation belt relativistic electrons during March 2013 geomagnetic storm
Chorus acceleration of radiation belt relativistic electrons during March 2013 geomagnetic storm
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DOI：
10.1002/2014ja019822
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发表时间：
2014-05
期刊：
影响因子：
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通讯作者：
F. Xiao;Chang Yang;Zhaoguo He;Z. Su;Qinghua Zhou;Yihua He;C. Kletzing;W. Kurth;G. Hospodarsky-G.-Hospod
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文献类型：
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作者：
F. Xiao;Chang Yang;Zhaoguo He;Z. Su;Qinghua Zhou;Yihua He;C. Kletzing;W. Kurth;G. Hospodarsky-G.-Hospod
最近发射的货车艾伦探测器为研究辐射带相对论电子的变化提供了前所未有的机会。在2013年3月17日至19日的风暴期间，货车艾伦探测器同时探测到强烈的合唱波和L = 4.5附近相对论性（2 − 4.5 MeV）电子通量的大幅增加。合唱波出现在0.1-0.5fce（电子赤道回转频率）的低频段，峰值频谱密度为<$10 −4 nT 2/Hz。相应地，相对论电子通量增加了102-103的因素相比，在恢复阶段的主要阶段的水平。通过对观测到的合唱光谱进行高斯拟合，计算出漂移和反弹平均扩散系数，然后用于求解二维福克-普朗克扩散方程。数值模拟表明，低波段合唱波确实在15小时内产生了相对论电子通量的巨大增强，与观测结果吻合良好。
The recent launching of Van Allen probes provides an unprecedent opportunity to investigate variations of the radiation belt relativistic electrons. During the 17–19 March 2013 storm, the Van Allen probes simultaneously detected strong chorus waves and substantial increases in fluxes of relativistic (2 − 4.5 MeV) electrons around L = 4.5. Chorus waves occurred within the lower band 0.1–0.5fce (the electron equatorial gyrofrequency), with a peak spectral density ∼10−4 nT2/Hz. Correspondingly, relativistic electron fluxes increased by a factor of 102–103 during the recovery phase compared to the main phase levels. By means of a Gaussian fit to the observed chorus spectra, the drift and bounce‐averaged diffusion coefficients are calculated and then used to solve a 2‐D Fokker‐Planck diffusion equation. Numerical simulations demonstrate that the lower‐band chorus waves indeed produce such huge enhancements in relativistic electron fluxes within 15 h, fitting well with the observation.