Research on pinching characteristics of electron beams emitted from different cathode surfaces of a rod-pinch diode

Journal Article · Thu Jul 15 04:00:00 EDT 2010 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3455536· OSTI ID:21389137

Yi, Gao ^[1]; Aici, Qiu; Zhong, Zhang; Pengfei, Zhang; Zhiguo, Wang; Hailiang, Yang ^[2]

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1. Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)
2. Northwest Institute of Nuclear Technology, P.O. Box 69-10, Xi'an 710024 (China)

The particle-in-cell code UNIPIC is used to simulate the working process of a rod-pinch diode and investigate the pinching characteristics of electron beams emitted from different cathode surfaces. The simulation results indicate that the electron beam emitted from the upstream surface pinches better than from other surfaces when all the three surfaces emit electrons. The charge-density deposition on the anode surface peaks at the rod tip while the deposited charge density is approximately uniform over the first 15 mm of the rod before rapidly increasing over the last 3 mm, indicating a large axial extent of electron deposition. For the case of single-surface emission, the pinching quality of the electron beam emitted from the downstream surface is better than those from other surfaces. The charge-density deposition peaks at the rod tip and decreases rapidly off the tip. Based on the relationship of Larmor radius, beam's self-magnetic field, and the spatial current distribution, the above simulation results are analyzed theoretically. The experiments are performed on the inductive voltage adder to examine the simulations. By comparing the axial distribution of the radiation on the anode rod measured with the pinhole camera and the on-axis forward x-ray dose measured with the LiF thermoluminescent detectors, the simulation results are verified. The electron emission suppression method and the impedance change for each case are investigated or discussed in this paper.

• OSTI ID: 21389137
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 7 Vol. 17; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAMS
CATHODES
DIODE TUBES
ELECTRODES
ELECTRON BEAMS
ELECTRON EMISSION
ELECTRON TUBES
EMISSION
LARMOR RADIUS
LEPTON BEAMS
MAGNETIC FIELDS
PARTICLE BEAMS
PINCH EFFECT
PLASMA DIAGNOSTICS
PLASMA SIMULATION
SIMULATION
SURFACES
THERMIONIC DIODES
THERMIONIC TUBES