Experiments for an eighth harmonic cusptron tube

Abstract

We have set up a cusptron device to compare the performance of π mode and 2π mode operation at 8th harmonic interaction. A concentric e-layer of of 30 Kev (γ=1.06) is produced for wave generation. For 2π mode operation, an 8-slotted waveguide with b/a = 22 is used, where b and a are the radii of the vane and the inner wall of the waveguide respectively. In order to achieve same output frequency for comparison, a 16-slotted waveguide with b/a =1.23 is used for π mode operation. The arrangement of the set up will be described. The preliminary results of the experiments will also be presented.