Please use this identifier to cite or link to this item:
http://hdl.handle.net/11375/18016
Title: | A Study of Flat Ring Emitter Electron Guns (Part B) |
Authors: | Harvey, Stanley Brooks |
Advisor: | Hutcheon, R. M. |
Department: | Engineering Physics |
Keywords: | flat, ring, emitting, cathode, electron, currents, emission |
Publication Date: | Sep-1976 |
Abstract: | <p> The design and performance of a flat emitting ring on-axis electron gun suitable for use in a small reflected beam accelerator was investigated. The design constraints include a low emittance (approximately 5π cm mrad), and a small beam size with a focus approximately 13 cm from the emitting surface.</p> <p> A suitable geometry was determined theoretically and was tested with a dispenser cathode. A beam with a focus at 12.7 ± 1 cm and an emittance of approximately 7π cm mrad was obtained. However, the dispenser cathode response time to heater current changes is too large for the required gun current control.</p> <p> Experiments were done to study the mechanical and thermal properties of flat emitting foil rings, since a directly heated foil has a fast response time. Two foils were tested: 1.27 x 10^-3 cm thick tungsten and 4.57 x 10^-4 cm thick tantalum. The present simple design requires impractically thin foils (≤ 0.25 microns thick) to reach emission temperatures at feasible heater currents.</p> |
Description: | This is Part B of the Thesis. |
URI: | http://hdl.handle.net/11375/18016 |
Appears in Collections: | Open Access Dissertations and Theses |
Files in This Item:
File | Description | Size | Format | |
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Harvey_Stanley_B._1976Sept_Masters..pdf | 1.57 MB | Adobe PDF | View/Open |
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