Design of a 10 MeV normal conducting CW proton linac based on equidistant multi-gap CH cavities

TL;DR

This paper proposes a compact 10 MeV CW proton linac design using equidistant multi-gap CH cavities, demonstrating stable beam acceleration up to 30 mA with manageable electromagnetic and thermal properties.

Contribution

It introduces a novel 10 MeV normal conducting CW proton linac design based on equidistant seven-gap CH cavities, addressing low energy acceleration challenges.

Findings

The linac length is less than 6 meters.

Maximum surface electric field is below 1.3 times Kilpatrick limit.

Capable of accelerating up to 30 mA beam with stable dynamics.

Abstract

The continue wave (CW) high current proton linac has wide applications as the front end of the high power proton machines. The low energy part is the most difficult one and there is no widely accepted solution yet. Based on the analysis of the focusing properties of the CW low energy proton linac, a 10 MeV low energy normal conducting proton linac based on equidistant seven-gap Cross-bar H-type (CH) cavities is proposed. The linac is composed of ten 7-gap CH cavities and the transverse focusing is maintained by the quadrupole doublets located between cavities. The total length of the linac is less than 6 meters and the average acceleration gradient is about 1.2 MeV/m. The electromagnetic properties of the cavities are investigated by Microwave Studio. At the nominal acceleration gradient the maximum surface electric field in the cavities is less than 1.3 times Kilpatrick limit, and the Ohmic loss of each cavity is less than 35 kW. The multi-particle beam dynamics simulations are performed with the help of the Tracewin code, the results show that the beam dynamics of the linac is quite stable, and the linac has the capability to accelerate up to 30 mA beam with acceptable dynamics behavior.