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Physics of Plasmas / Volume 18 / Issue 1 / ARTICLES / Basic Plasma Phenomena, Waves, Instabilities

Phys. Plasmas 18, 012105 (2011); http://dx.doi.org/10.1063/1.3533440 (9 pages)

Transit time instabilities in an inverted fireball. II. Mode jumping and nonlinearities

R. L. Stenzel1, J. Gruenwald2, B. Fonda2, C. Ionita2, and R. Schrittwieser2

1Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA
2Institute for Ion Physics and Applied Physics, Leopold-Franzens University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria

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(Received 15 October 2010; accepted 13 December 2010; published online 11 January 2011)

A fireball is formed inside a highly transparent spherical grid immersed in a dc discharge plasma. The ambient plasma acts as a cathode and the positively biased grid as an anode. A strong nearly current-free double layer separates the two plasmas. Electrons are accelerated into the fireball, ionize, and establish a discharge plasma with plasma potential near the grid potential. Ions are ejected from the fireball. Since electrons are lost at the same rate as ions, most electrons accelerated into the fireball just pass through it. Thus, the electron distribution contains radially counterstreaming electrons. High-frequency oscillations are excited with rf period given by the electron transit time through the fireball. Since the frequency is well below the electron plasma frequency, no eigenmodes other than a beam space-charge wave exists. The instability is an inertial transit-time instability similar to the sheath-plasma instability or the reflex vircator instability. In contrast to vircators, there is no electron reflection from a space-charge layer but counterstreaming arises from spherical convergence and divergence of electrons. While the basic instability properties have been presented in a companion paper [ R. L. Stenzel et al., Phys. Plasmas 18, 012104 (2011) ], the present paper focuses on observed mode jumping and nonlinear effects. The former produce frequency jumps and different potential profiles, the latter produce harmonics associated with electron bunching at large amplitudes. In situ probe measurements are presented and interpreted.

© 2011 American Institute of Physics

Article Outline

  1. INTRODUCTION
  2. SUMMARY OF THE EXPERIMENTAL ARRANGEMENT
  3. EXPERIMENTAL OBSERVATIONS
    1. Pulsating fireballs
    2. Frequency and mode jumping
    3. Harmonic generation
  4. SUMMARY AND CONCLUSIONS

EDITORIALLY RELATED

  1. Transit time instabilities in an inverted fireball. I. Basic properties
    R. L. Stenzel et al.
    Phys. Plasmas 18, 012104 (2011)PHPAEN000018000001012104000001

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KEYWORDS and PACS

Keywords

high-frequency discharges, Langmuir probes, plasma instability, plasma nonlinear processes, plasma oscillations, plasma sheaths, plasma transport processes

PACS

  • 52.35.-g

    Waves, oscillations, and instabilities in plasmas and intense beams

  • 52.35.Mw

    Nonlinear phenomena: waves, wave propagation, and other interactions (including parametric effects, mode coupling, ponderomotive effects, etc.)

  • 52.40.Mj

    Particle beam interactions in plasmas

  • 52.59.Bi

    Grid- and ion-diode-accelerated beams

  • 52.59.Ye

    Plasma devices for generation of coherent radiation

ARTICLE DATA

Digital Object Identifier
http://dx.doi.org/10.1063/1.3533440

PUBLICATION DATA

ISSN

1070-664X (print)  
1089-7674 (online)

Publisher

$abstract.society.value is a Member of CrossRef American Institute of Physics

For access to fully linked references, you need to log in.
    J. R. Pierce, J. Appl. Phys. 15, 721 (1944)JAPIAU000015000010000721000001.

    R. L. Stenzel, Phys. Fluids B 1, 2273 (1989)PFBPEI000001000011002273000001.

    L. Conde and L. Leon, Phys. Plasmas 1, 2441 (1994)PHPAEN000001000008002441000001.

    S. C. Burkhart, R. D. Scarpetti, and R. L. Lundberg, J. Appl. Phys. 58, 28 (1985)JAPIAU000058000001000028000001.

    L. Li, L. Liu, G. Cheng, Q. Xu, H. Wan, L. Chang, and J. Wen, J. Appl. Phys. 105, 123301 (2009)JAPIAU000105000012123301000001.

    R. L. Stenzel, J. Gruenwald, B. Fonda, C. Ionita, and R. Schrittwieser, Phys. Plasmas 18 012104 (2011)PHPAEN000018000001012104000001.

    A. Krokhmal, J. Z. Gleizer, Y. E. Krasik, V. T. Gurovich, and J. Felsteiner, J. Appl. Phys. 95, 3304 (2002)JAPIAU000095000007003304000001.

    R. A. Filatov, A. E. Hramov, Y. P. Bliokh, A. A. Koronovskii, and J. Felsteiner, Phys. Plasmas 16, 033106 (2009)PHPAEN000016000003033106000001.


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