Critical current dependence on geometry in the self-magnetic-pinch radiographic diode

Author

Martin, Patrick ; Threadgold, Jim

Author_Institution

Atomic Weapons Establ., Aldermaston, UK

fYear

2012

fDate

8-13 July 2012

Abstract

The self-magnetic-pinch (SMP) diode is an intense x-ray source for pulsed power driven radiographic systems. This electron beam diode is a critical current limited device often described using equations derived from analytic approximations to large aspect ratio (cathode diameter to anode-cathode gap) variant diodes. A factor, α, is usually used to account for changes in space charge limited electron emission due to the presence of positive ions in the emission region and for the details of the geometry of the diode. The critical current dependence on geometry in the SMP diode has been investigated using the Large-Scale-Plasma (LSP) Particle-in-Cell (PiC) code and results are presented.

Keywords

cathodes; critical currents; electron emission; pinch effect; plasma diodes; plasma simulation; plasma transport processes; radiography; space charge; SMP diode; analytic approximation; anode-cathode gap; cathode diameter; critical current limited device; diode geometry; electron beam diode; emission region; intense X-ray source; large-scale-plasma particle-in-cell code; positive ion; pulsed power driven radiographic system; self-magnetic-pinch radiographic diode; space charge limited electron emission; Atomic measurements; Critical current; Electron beams; Geometry; Plasmas; Radiography; Weapons;

fLanguage

English

Publisher

ieee

Conference_Titel

Plasma Science (ICOPS), 2012 Abstracts IEEE International Conference on

Conference_Location

Edinburgh

ISSN

0730-9244

Print_ISBN

978-1-4577-2127-4

Electronic_ISBN

0730-9244

Type

conf

DOI

10.1109/PLASMA.2012.6383602

Filename

6383602