ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
Plasma diagnostics employing energetic lithium beams are in routine use on several present-day tokamak experiments. These measurements are constrained by the availability of a suitable lithium ion source. Necessary and/or desirable parameters include narrow energy spread, high-emission current density, simplicity, and long lifetime. The existing ion gun on the TEXT experiment uses the thermionic emitter β-eucryptite and meets the above requirements, except for being limited to a useful emission of about 4 mA. We will present design criteria and accelerator results for a new ion gun capable of 15-mA emission based on an increased emitter area. Important design considerations are the thermal and mechanical properties of the large (∼20 cm2) emitter area and the ion optics required to focus the emitted flux into a beam of ∼1-cm2 cross section. The potential improvement in the performance of both the TEXT and ASDEX diagnostic systems will be discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1140095