中国物理B ›› 2018, Vol. 27 ›› Issue (8): 85201-085201.doi: 10.1088/1674-1056/27/8/085201

• PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES • 上一篇    下一篇

Observation of double pseudowaves in an ion-beam-plasma system

Zi-An Wei(卫子安), Jin-Xiu Ma(马锦秀), Kai-Yang Yi(弋开阳)   

  1. Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, China
  • 收稿日期:2018-04-19 修回日期:2018-05-11 出版日期:2018-08-05 发布日期:2018-08-05
  • 通讯作者: Jin-Xiu Ma E-mail:jxma@ustc.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11575183 and 11705201).

Observation of double pseudowaves in an ion-beam-plasma system

Zi-An Wei(卫子安), Jin-Xiu Ma(马锦秀), Kai-Yang Yi(弋开阳)   

  1. Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, China
  • Received:2018-04-19 Revised:2018-05-11 Online:2018-08-05 Published:2018-08-05
  • Contact: Jin-Xiu Ma E-mail:jxma@ustc.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11575183 and 11705201).

摘要:

Pseudowaves, known as burst-ion signals, which are different from plasma normal modes, exist frequently in ion-wave excitation experiments when launching the waves by applying a pulsed voltage to a negatively biased grid. In previous experiments, only one kind of the pseudowave was observed. In this paper, we report the observation and identification of double pseudowaves in an ion-beam-plasma system. These pseudowaves originate from two ion groups:the burst of the beam ions and the burst of the background ions. It was observed that the burst of the background ions was in the case of high ion beam energy, while the burst of the beam ions was in the case of low ion beam energy. By observing the dependence of the signal velocities on the characteristics of the excitation voltage, these pseudowaves can be identified. It was also observed that the burst ion signal originating from the background ions can interact with slow beam mode and that originating from the beam ions can interact with fast beam mode.

关键词: ion-beam-plasma system, normal modes, pseudowaves, wave-particle interaction

Abstract:

Pseudowaves, known as burst-ion signals, which are different from plasma normal modes, exist frequently in ion-wave excitation experiments when launching the waves by applying a pulsed voltage to a negatively biased grid. In previous experiments, only one kind of the pseudowave was observed. In this paper, we report the observation and identification of double pseudowaves in an ion-beam-plasma system. These pseudowaves originate from two ion groups:the burst of the beam ions and the burst of the background ions. It was observed that the burst of the background ions was in the case of high ion beam energy, while the burst of the beam ions was in the case of low ion beam energy. By observing the dependence of the signal velocities on the characteristics of the excitation voltage, these pseudowaves can be identified. It was also observed that the burst ion signal originating from the background ions can interact with slow beam mode and that originating from the beam ions can interact with fast beam mode.

Key words: ion-beam-plasma system, normal modes, pseudowaves, wave-particle interaction

中图分类号:  (Waves, oscillations, and instabilities in plasmas and intense beams)

  • 52.35.-g
52.35.Fp (Electrostatic waves and oscillations (e.g., ion-acoustic waves)) 52.35.Qz (Microinstabilities (ion-acoustic, two-stream, loss-cone, beam-plasma, drift, ion- or electron-cyclotron, etc.)) 52.20.-j (Elementary processes in plasmas)