First mm-wave generation in the FOM free electron maser

Author

Verhoeven, A.G.A. ; Bongers, W.A. ; Bratman, V.L. ; Caplan, M. ; Denisov, G.G. ; van der Geer, C.A.J. ; Manintveld, P. ; Poelman, A.J. ; Plomp, Johan ; Savilov, A.V. ; Smeets, P.H.M. ; Sterk, A.B. ; Urbanus, W.H.

Author_Institution

FOM Inst. for Plasma Phys., Nieuwegein, Netherlands

Volume

2

fYear

1998

fDate

17-21 Aug 1998

Firstpage

751

Abstract

A free electron maser (FEM) has been built as a pilot experiment for a mm-wave source for applications on future fusion research devices such as ITER, the International Tokamak Experimental Reactor. A unique feature of the Dutch Fusion-FEM is the possibility to tune the frequency over the entire range from 130 to 260 GHz at an output power exceeding 1 MW. In the first phase of the project, the so-called inverse set-up is used. The electron gun is mounted inside the high-voltage terminal. The entire beam line was tested successfully with extremely low loss current, lower than 0.05%. First generation of mm-waves was achieved in October 1997. Up to now the highest peak power measured is 700 kW at 200 GHz. This was achieved with a beam current of 8 A and an accelerator voltage of 1.77 MV. Output power, start-up time and frequency correspond well with simulation results. Parameter scans for the longitudinal undulator gap, accelerator voltage and reflection coefficient have given a wide range of interesting data of which a few highlights are given

Keywords

Tokamak devices; electron guns; electrostatic accelerators; fusion reactor design; masers; microwave generation; plasma radiofrequency heating; 1.77 MV; 130 to 260 GHz; 700 kW; 8 A; Dutch Fusion-FEM; FOM free electron maser; ITER; International Tokamak Experimental Reactor; accelerator voltage; beam line testing; electron gun; frequency; frequency tuning; fusion research devices; high-voltage terminal; inverse set-up; longitudinal undulator gap; mm-wave generation; output power; peak power measurement; reflection coefficient; start-up time; Electrons; Frequency; Fusion power generation; Inductors; Masers; Power generation; Power measurement; Testing; Tokamaks; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Discharges and Electrical Insulation in Vacuum, 1998. Proceedings ISDEIV. XVIIIth International Symposium on

Conference_Location

Eindhoven

ISSN

1093-2941

Print_ISBN

0-7803-3953-3

Type

conf

DOI

10.1109/DEIV.1998.738872

Filename

738872