A novel electron beam diagnostic using the measurement of the cyclotron emission (ECE)
A new method for the measurement of the parallel momentum distribution function of a monönergetic, magnetised, weakly relativistic electron beam is presented. A gyrating electron having a parallel velocity beta(parallel) emits radiation at a Doppler shifted freqüncy given by w = w(0)[1-beta(parallel)cos theta/l where theta is the observation angle and w(0) = qB/m. Therefore, at a given theta, the measurement of the emitted spectrum of an electron beam gives, in a straightforward manner, the distribution function in beta(parallel). In the analysis relativistic effects on the angular distribution of the emission are taken into account as well as the experimental constraints such as the angular dependency of the gain of the antenna used for the detection. Experimental results are presented for a 70 keV annular electron beam.
Bibliographic Reference: Paper presented: Fourteenth International Conference on Infrared and Millimeter Waves, Würzburg (DE), Oct. 2-6, 1989
Availability: Available from (1) as Paper EN 35214 ORA
Record Number: 199010928 / Last updated on: 1994-12-01
Original language: en
Available languages: en