Volume 77, Number 4, February 2007
Article Number 45001
Number of page(s) 4
Section Physics of Gases, Plasmas and Electric Discharges
Published online 13 February 2007
EPL, 77 (2007) 45001
DOI: 10.1209/0295-5075/77/45001

Dissipative instability of overlimiting electron beam in a nonuniform$\hbox{--} $cross-section waveguide

E. V. Rostomyan

Institute of Radiophysics and Electronics, National Academy of Sciences of Armenia - 1 Alikhanyan str., Ashtarack, 378410, Armenia

received 12 September 2006; accepted in final form 12 December 2006; published February 2007
published online 13 February 2007

The effect of dissipation on the instability caused by growing of the slow space charge wave of electron beam is studied. High level of dissipation leads to a new type of dissipative streaming instability. Its growth rate has a previously unknown, inverse proportional dependence on dissipation. The new dependence is a result of superposition of two factors, both of which lead to excitation of the beam wave with negative energy: increasing of beam current and dissipation. Basic parameters of the instability indicate that it can be an important additional factor upon design of high-power high-frequency devices based on relativistic e-beams.

52.35.-g - Waves, oscillations, and instabilities in plasmas and intense beams.

© Europhysics Letters Association 2007