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Pulsed electron source characterization with the modified three gradient method

S. Marghitu·C. Oproiu·C. Dinca·O. Marghitu
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Abstract

Results from the Modified Three Gradient Method (MTGM), applied to a pulsed high intensity electron source, are presented. The MTGM makes possible the non-destructive determination of beam emittance in the space charge presence [1]. We apply the MTGM to an experimental system equipped with a Pierce convergent diode, working in pulse mode, and having a directly heated cathode as electron source. This choice was mainly motivated by the availability of an analytical characterization of this source type [2], as well as the extended use of the Pierce type sources in linear accelerators. The experimental data are processed with a numerical matching program, based on the K-V equation for an axially symmetric configuration [3], to determine the emittance and object cross-over position and diameter. The variation of these parameters is further investigated with respect to both electrical and constructive characteristics of the source: cathode heating current, extraction voltage, and cathode-anode distance.

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S. Marghitu, C. Oproiu, C. Dinca, O. Marghitu. 2001-11-10. Pulsed electron source characterization with the modified three gradient method. https://arxiv.org/abs/physics/0111099

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