Design of the low energy beam transport line for the China spallation neutron source

• Published in: Chinese physics C Vol. 32; no. 3; pp. 227 - 231
• Main Author: 李金海 欧阳华甫 傅世年 张华顺 何伟
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.03.2008; Institute of High Energy Physics, CAS, Beijing 100049, China
• Subjects: 低能束流传输; 射频四极; 散变中子源; 离子源; LEBT; CSNS; steerer; space charge; chopper
• ISSN: 1674-1137; 0254-3052; 2058-6132
• DOI: 10.1088/1674-1137/32/3/014

The design of the China Spallation Neutron Source （CSNS） low-energy beam transport （LEBT） line, which locates between the ion source and the radio-frequency quadrupole （RFQ）, has been completed with the TRACE3D code. The design aims at perfect matching, primary chopping, a small emittance growth and sufficient space for beam diagnostics. The line consists of three solenoids, three vacuum chambers, two steering magnets and a pre-chopper. The total length of LEBT is about 1.74 m. This LEBT is designed to transfer 20 mA of H-pulsed beam from the ion source to the RFQ. An induction cavity is adopted as the pre-chopper. The electrostatic octupole steerer is discussed as a candidate. A four-quadrant aperture for beam scraping and beam position monitoring is designed.