137-GHz gyrotron diagnostic for instability studies in Tara

Journal Article · Fri Aug 01 04:00:00 EDT 1986 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1138813· OSTI ID:5642252

Machuzak, J S; Woskoboinikow, P; Mulligan, W J; Cohn, D R; Gerver, M; Guss, W; Mauel, M; Post, R S; Temkin, R J

A narrow linewidth (<100 kHz), 1-kW, 137-GHz gyrotron and an efficient TE/sub 03/ to TE/sub 11/ cylindrical waveguide mode converter set (>97% TE/sub 11/ 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 (n-italic-tilde/n-italic<10/sup -6/) to be detected above this background during ECRH in the plugs.

• Research Organization: Plasma Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
• OSTI ID: 5642252
• Journal Information: Rev. Sci. Instrum.; (United States), Journal Name: Rev. Sci. Instrum.; (United States) Vol. 57:8; ISSN RSINA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
700208 -- Fusion Power Plant Technology-- Inertial Confinement Technology
AMPLIFIERS
ECR HEATING
ELECTRONIC EQUIPMENT
EMISSION SPECTROSCOPY
EQUIPMENT
FLUCTUATIONS
HEATING
HIGH-FREQUENCY HEATING
INELASTIC SCATTERING
INSTABILITY
LIGHT SCATTERING
MAGNETIC MIRRORS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
OPEN PLASMA DEVICES
OPTICAL SYSTEMS
PLASMA DENSITY
PLASMA DIAGNOSTICS
PLASMA HEATING
PLASMA INSTABILITY
SCATTERING
SPECTROSCOPY
TANDEM MIRRORS
TARA DEVICES
THERMONUCLEAR DEVICES
THOMSON SCATTERING
VARIATIONS