Investigations Into the Role of the Bremsstrahlung Conversion Target in the Self-Magnetic Pinch Radiographic Diode

• Published in: IEEE transactions on plasma science Vol. 39; no. 10; pp. 1943 - 1948
• Main Authors: Martin, P. N., Threadgold, J. R., Jones, A., McLean, J., Cooper, G. M., Webb, K., Jeffries, G., Juniper, P.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-10-2011; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Anodes; Assembly; Bremsstrahlung; Conversion; Diodes; Electron beams; Electrons; Focusing; Foils; Impedance; ion beams; Materials; particle beams; Plasmas; Radiography; Simulation; Simulators
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2011.2163734

In order to understand the role of the Bremsstrahlung conversion target assembly of the self-magnetic pinch diode, an investigation is undertaken on the Energetic Radiation On/Off Simulator machine at the Atomic Weapons Establishment. The first phase of this investigation focuses on altering the conversion target material and foil-to-conversion-target separation, with electrical records being used to look at the change in bipolar flow within the diode. The shape of the conversion target was also altered such that it formed a band allowing the amount of conversion material to be varied while still allowing a radiographic spot to be measured. The second phase of this work includes data and discussion on the role of the foil which sits in front of the high-atomic-number target. The conclusions of these investigations are that the conversion target is not required in order for the diode to operate, the quantitative degree of pinch experienced by the electron beam is not dependent on the presence of the conversion target, and the first metal surface is the key factor in the transport and focusing of the electron beam.