Design of an electron gun for terahertz radiation source

TL;DR

This paper presents the design of an electron gun integrated with an EC-ITC RF gun to produce short, high-current electron bunches for terahertz radiation, emphasizing beam quality and compression.

Contribution

It introduces a specific gridded DC gun structure that effectively generates high-current, short-duration electron beams suitable for terahertz sources.

Findings

Successfully generated 6 μs beam with 4.5A current.

Achieved electron energy of up to 15 KeV for effective beam compression.

Demonstrated the feasibility of the designed electron gun structure.

Abstract

With the aim to obtain short-pulse bunches with high peak current for a terahertz radiation source, an EC-ITC (External-Cathode Independently Tunable Cells) RF gun was employed. As the external injecting electron source of the ITC RF gun, a gridded DC gun plays a key role, the performance of which determines the beam quality in the injector and transport line. In order to make the beam well compressed in the ITC RF gun, the energy of the electrons acquired from the gridded DC gun should be 15 KeV at most. A proper structure of the gridded gun is shown to overcome the strong space- charge force on the cathode, which is able to generate 6 {\mu}s beam with 4.5A current successfully.