Phase contrast method as an imaging diagnostic for plasma density fluctuations (invited)

Journal Article · Mon Aug 01 00:00:00 EDT 1988 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1140193· OSTI ID:6906384

Weisen, H

An imaging diagnostic for the observation of plasma density fluctuations is presented. It is based on the phase contrast method, and is used on the TCA tokamak to investigate fluctuations associated with plasma turbulence and driven waves in radio frequency heating experiments. The diagnostic uses a 23-cm-wide CO/sub 2/ laser beam transmitted through the plasma, and produces an image of the plasma where the small phase shifts (chemically bondphichemically bondapprox.10/sup -5/ to 10/sup -3/) due to refractive perturbations are revealed as corresponding intensity variations. A wide range of fluctuation wavelengths between 0.2 and about 20 cm is accessible to observation, with a sensitivity better than 10/sup -5/ rad for a 1-MHz bandwidth.

• Research Organization: Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, Ecole Polytechnique Federale de Lausanne, 21, Avenue des Bains, CH-1007 Lausanne, Switzerland
• OSTI ID: 6906384
• Journal Information: Rev. Sci. Instrum.; (United States), Vol. 59:8
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
PLASMA DIAGNOSTICS
LIGHT SCATTERING
PLASMA DENSITY
TCA TOKAMAK
IMAGES
INFRARED RADIATION
LIGHT TRANSMISSION
PHASE SHIFT
CLOSED PLASMA DEVICES
ELECTROMAGNETIC RADIATION
RADIATIONS
SCATTERING
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
700102* - Fusion Energy- Plasma Research- Diagnostics