ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
A narrow linewidth (〈100 kHz), 1-kW, 137-GHz gyrotron and an efficient TE03 to TE11 cylindrical waveguide mode converter set (〉97% TE11 mode output) have been built for collective Thomson scattering diagnostics. The main goal will be to study instability driven ion density fluctuations in the Tara plug such as the drift cyclotron loss cone (DCLC), the axial loss cone (ALC), harmonics of the DCLC and ALC, and the ion two-stream instability. The heterodyne receiver and signal optics have been installed on Tara. Background electron cyclotron emission (ECE) at 139±1.5 GHz after electron cyclotron resonance heating (ECRH) in the Tara plug corresponded to equivalent blackbody temperatures of 453 and 70 eV for extraordinary and ordinary emission, respectively. The well-collimated receiver field of view completely through the Tara plug has allowed for excellent polarization discrimination of the ECE. The high-power capability of this gyrotron will allow weak fluctuation levels (ñ/n〈10−6) to be detected above this background during ECRH in the plugs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1138813
