Detection of plasma equilibrium shifts with fiber-optic sensing of image currents

Journal Article · Mon Aug 01 04:00:00 EDT 1988 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1140176· OSTI ID:6903858

Forman, P R; Jahoda, F C; Miller, G

Plasma shifts generate opposite-polarity net shell image currents at diametrically opposed shell locations. In theory these image currents can be detected by Faraday rotation fiber-optic current sensors wound around the shell sections. In practice the validity of the measurement depends on the extent of suppression of the linear birefringence induced by the fiber coil bending and lateral pressure. Circular birefringence bias twist of 60 turns/m of 125-..mu..m o.d. single-mode fiber is sufficient for 2-in. radii of curvature bends, in agreement with theory, while 100 turns/m of 80-..mu..m o.d. fiber have not been successful with 1-in. radii of curvature, contrary to calculations. Different means for further suppression of linear birefringence are discussed.

• Research Organization: Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545
• OSTI ID: 6903858
• Journal Information: Rev. Sci. Instrum.; (United States), Journal Name: Rev. Sci. Instrum.; (United States) Vol. 59:8; ISSN RSINA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
BIREFRINGENCE
CLOSED PLASMA DEVICES
COMPACT TORUS
ELECTRO-OPTICAL EFFECTS
FARADAY EFFECT
FIBERS
FIELD-REVERSED THETA PINCH DEVICES
OPTICAL FIBERS
PINCH DEVICES
PLASMA DIAGNOSTICS
REFRACTION
THERMONUCLEAR DEVICES
TORI