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DOE OSTI · 1876769

Magnetic-Field Diffusion Effects in Beam Position Monitors I: Theory

Ekdahl, Jr., Carl August·Broste, William B.·Johnson, Jeffrey B.
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Abstract

Beam position monitors (BPMs) provide time-resolved measurements of the current and centroid position of high-current electron beams in linear induction accelerators (LIAs). One of the types of detectors used in BPMs is the B-dot loop, which generates a signal from the EMF due to the time varying magnetic flux through the loop. If some of the boundaries of the loop are composed of thick metal walls with finite conductivity, the resulting signal must be corrected for the magnetic field diffusion into the metal. The theoretically predicted flux due to diffusion is in remarkable agreement with experimental measurements

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46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGYbeam position monitorscurrent measurementselectron-beam diagnosticsLinear induction acceleratorsmagnetic diffusion

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Ekdahl, Jr., Carl August, Broste, William B., Johnson, Jeffrey B.. 2022-07-15. Magnetic-Field Diffusion Effects in Beam Position Monitors I: Theory. https://doi.org/10.2172/1876769

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