Research support for plasma diagnostics on Elmo Bumpy Torus: investigation of diamagnetic diagnostics for the electron rings

Technical Report · Sun Feb 01 00:00:00 EST 1981

DOI:https://doi.org/10.2172/6562540· OSTI ID:6562540

Carpenter, K. H.

Diamagnetic diagnostics for the EBT electron rings are fundamental to the experiment. The diamagnetic flux pickup loops on each cavity output signals proportional to ring perpendicular energy. A data analysis technique is described, which in its simplest form is subtracting 1/4 the signal from each neighboring cavity pickup loop from the central one's, which provides a signal proportional to the energy in a single ring. The calibration factor relating absolute perpendicular energy to diamagnetic signal depends weakly on the geometrical model for the ring. Calculations with a bumpy cylinder MHD equilibrium code give calibration factors in reasonable agreement (20%) to the values obtained using a simple, concentric cylindrical current sheet model. The cylindrical current sheet model is used to show that diamagnetic field components measured external to the plasma require high precision or correlation with other diagnostics in order to fix model parameters. A computer simulation shows an assumption of constant ring thickness and energy density with increasing length (and energy) is compatible to diamagnetic field observations on NBT.

• Research Organization: Missouri Univ., Rolla (USA). Dept. of Electrical Engineering
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 6562540
• Report Number(s): ORNL/Sub-7676/1; TRN: 81-007112
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ELMO BUMPY TORUS
ELECTRON RINGS
COMPUTERIZED SIMULATION
MAGNETIC PROBES
MAGNETOHYDRODYNAMICS
PLASMA DIAGNOSTICS
PLASMA DIAMAGNETISM
DIAMAGNETISM
ELMO DEVICES
FLUID MECHANICS
HYDRODYNAMICS
MAGNETIC MIRRORS
MAGNETISM
MECHANICS
OPEN PLASMA DEVICES
PROBES
SIMULATION
THERMONUCLEAR DEVICES
700102* - Fusion Energy- Plasma Research- Diagnostics