Self-bearing membrane exit window with the separate anode for sub-microsecond electron accelerator. (March 2020)

• Record Type: Journal Article
• Authors: Egorov, Ivan; Poloskov, Artem; Serebrennikov, Maksim; Remnev, Gennady
• Is Part Of: Vacuum. Volume 173(2020)
• Publication Date: 2020-03
• Subjects: Vacuum electron diode -- Electron beam extraction -- Accelerator exit window -- Sealing membrane -- Output window; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2019.109111
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: A vacuum electron diode of a sub-microsecond pulsed electron accelerator with various cooled air-water exit window designs were tested in single-pulse and high-repetition-rate modes. A well-known exit window construction with metal membrane and supporting grid was tested for 10 4 electron beam pulses at 10 pps before crashing with vacuum failure. A design with a self-bearing anode-membrane demonstrated 10 5 pulses durability without vacuum failure at 40 pps but accumulated damage like foil sag, overheating areas and surface discharge marks. The combined design of an exit window with an anode-grid and a self-bearing membrane demonstrated a lifetime of more than 10 6 beam pulses at 40 pps operation. Highlights: Overheating of the grid supporting the membrane of the exit window leads to its destruction at high repetition rate mode. The gridless exit window is cooled effectively but has non-planar configuration of an accelerating gap that reduces lifetime. The exit window with an anode-grid separated from a self-bearing membrane provides >10 6 beam pulses lifetime at 40 pps mode.