Excitation of Electromagnetic Waves by an Electron Ring Beam in a Magnetized Plasma Waveguide

作     者：周国成 吴京生 等 

作者机构：CenterforSpaceScienceandAppliedResearchChineseAcademyofSciencesBeijing100080 DepartmentofEarthandSpaceSciencesUniversityofScienceandTechnologyofCHinaHefei230026 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2002年第19卷第10期

页      面：1556-1559页

核心收录：

学科分类：07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 070204[理学-等离子体物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：中国科学院知识创新工程重要方向项目 国家自然科学基金 

主　　题：Circular waveguides 

摘      要：We study the resonant interactions between an electron ring beam and plasma waveguide modes. This is motivated by the research ofradio emission in low solar corona. We consider a density-depleted duct (above an active region near a flare site) that may be treated as amagnetized plasma waveguide. The electromagnetic waves excited in the waveguide are classified into the so-calledE-type andB-type waves. The results show that there are two unstable modes ofB-type waves propagating parallel and anti-parallel to the direction of theelectron beam. The effect of the finite radius and boundary conditions of the waveguide on the excitation of waveguide modes isimportant. For a givenB-type mode, the smaller the radiusR, the larger the temporal and spatial amplification rate. We suggest thatthese excited waveguide modes could be one of the processes responsible for the observed solar radio emission.