教師資料查詢 | 類別: 會議論文 | 教師: 汪愷悌 WANG KAITI (瀏覽個人網頁)

標題:Landau resonance between electrons and lower-hybrid waves in the inner magnetosphere
學年105
學期2
發表日期2017/05/20
作品名稱Landau resonance between electrons and lower-hybrid waves in the inner magnetosphere
作品名稱(其他語言)
著者Fumiko Otsuka; Kaiti Wang; Shuichi Matsukiyo; Tohru Hada
作品所屬單位
出版者
會議名稱JpGU-AGU Joint Meeting 2017
會議地點Chiba, Japan
摘要Lower-hybrid waves are frequently observed near the geomagnetic equator in the inner magnetosphere (i.e., equatorial noise). They are in the frequency range between the proton gyrofrequency and the LH frequency, and were found to propagate approximately perpendicular to the background magnetic field with almost linear polarization. We have focused on the capability of the LH waves to scatter electrons, and showed that the diffusions could occur via both cyclotron and Landau resonances. To have the cyclotron resonance to occur, the electron energies should be higher than 1.56 MeV. On the contrary, the Landau resonance occurs even for relatively lower energies from 1.4 keV. Here, the linear resonance condition is assumed under the observed LH wave parameters such as the propagation angle of 85 degree and the frequency of 130 Hz in a plasma environment with the Alfven velocity of 1150 km/s.

In this presentation, we discuss the Landau resonance between electrons and LH waves, by performing test particle simulation. The LH waves are given as a superposition of sinusoidal waves with different frequencies propagating highly perpendicular to the background magnetic field. The given waves obey the cold plasma dispersion relation. We evaluate the pitch-angle diffusion coefficient of electrons with energies from a few eV to 1 MeV. We discuss changes in pitch-angle distributions related to the diffusion processes.
關鍵字pitch-angle diffusion;electron;lower-hybrid wave;inner magnetosphere
語言英文
收錄於
會議性質國際
校內研討會地點
研討會時間20170520~20170525
通訊作者Otsuka, Fumiko
國別日本
公開徵稿
出版型式
出處PEM16-P25, Abstracts of JpGU-AGU Joint Meeting 2017
相關連結
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