Cyclotron maser instability for general magnetic harmonic number
Journal
Physics of Fluids
Journal Volume
21
Journal Issue
10
Pages
1877-1886
Date Issued
1978
Author(s)
Abstract
The cyclotron maser instability for general magnetic harmonic number transverse electric (TE) and transverse magnetic (TM) waveguide modes in a conducting cylinder of radius Rc are examined. The analysis is carried out for a hollow electron beam (radius R0) propagating parallel to a uniform axial magnetic field B0êz. It is assumed that v/γ0<1, where v is Budker's parameter and γ0mc2 is the electron energy in a frame of reference moving with the beam axial velocity βbcêz. One of the most important features of the analysis is that the instability growth rate for magnetic harmonic numbers s = 2,3,... is comparable to the growth rate of the fundamental (s = 1) mode, particularly for moderate electron energy [β0 = (1 -1/γ02)1/2≳ 0.4]. Moreover, it is shown that the instability growth rate can be maximized by appropriate choice of the geometric parameter R0/Rc. © 1978 American Institute of Physics.
SDGs
Type
journal article