Determination of the electron beam velocity in a gyrotron by means of Thomson scattering
In experimental investigations of gyrotrons an important discrepancy between the theoretically predicted efficiency and measured values has been observed. Since the energy conversion efficiency depends critically on the electron velocity, it is important to be able to measure the latter. A non-intrusive measurement is only possible with optical methods. Thomson scattering of laser radiation from electrons has become a standard diagnostic method in plasma physics for measuring the electron temperature. This method is applied in order to determine the relativistic electron velocity in a 100 GHz quasi-optical gyrotron. The major problem in this experiment is related to the low electron density in the beam, resulting in a very weak scattered laser signal. It is therefore of paramount importance to optimise the scattering geometry for maximum light collection. The overall performance of the proposed experiment is discussed and spectra calculated according to the theory of Zhuravlev et al. are presented.
Bibliographic Reference: Paper presented: 16th International Conference on Infrared and Millimeter Waves, Lausanne (CH), August 26-30, 1991
Availability: Available from (1) as Paper EN 36306 ORA
Record Number: 199210226 / Last updated on: 1994-12-02
Original language: en
Available languages: en