We have constructed a Cerenkov maser oscillator designed to operate at 16.9 GHz with a solid electron beam accelerated to 70 kV, using an alumina tube, fitted into a copper pipe. The measurements of the dispersion curves for such a cavity of various dielectrically loaded structures are presented. A method for calculating efficiently the dispersion curve of a cylindrical Cerenkov free electron device having a small gap between the dielectric liner and the waveguide wall is also described. In any practical realisation, such a gap cannot be avoided and the results obtained here indicate that the dispersion curve can be very sensitive to its thickness.
Published in:
Pulsed Power Conference, 2003. Digest of Technical Papers. PPC-2003. 14th IEEE International
(Volume:2
)
Date of Conference: 15-18 June 2003