9–13 Sept 2024
Wanda Realm Beijing
Asia/Shanghai timezone
IBIC2024 Final Proceedings: https://accelconf.web.cern.ch/ibic2024/

Direct measurement of the longitudinal emittance for a proton beam at exit of a radio frequency quadrupole

THCC2
12 Sept 2024, 14:00
20m
China Hall 2 (Auditoriium)

China Hall 2

Auditoriium

Contributed Oral Presentation MC5: Longitudinal Diagnostics and Synchronization THC: Longitudinal Diagnostics and Synchronization

Speaker

Yong Zhang (Institute of Modern Physics, Chinese Academy of Sciences)

Description

Clarifying the longitudinal phase space distribution at the exit of a radio frequency quadrupole (RFQ) is crucial for precise beam tuning to minimize beam loss in a high-power superconducting linac. In this contribution, we introduce a method for direct measurement of the longitudinal emittance of a proton beam at the RFQ exit, which delivers an output energy of 1.51 MeV. Initially, we developed a bunch shape monitor (BSM) inspired by Feschenko’s design, achieving a resolution of 20 picoseconds. To conduct the direct measurement of longitudinal emittance, we integrate this BSM with a waist-to-waist beam transfer matrix, an energy-spread dipole, and a horizontal slit with a 0.2 mm width. The horizontal slit is positioned at the first waist at the dipole’s input, while the BSM wire is situated at the second waist, at the dipole’s output. This arrangement, enhanced by the waist-to-waist transfer matrix, improves the energy spread resolution to 0.01%. Using the BSM wire, we measure the energy spread and horizontal profile. Through adjusting the buncher voltage and synchronous phase, we use dipole and BSM to measure different longitudinal emittances and ascertain the effects of bunching and debunching conditions on the longitudinal phase space. Consequently, this comprehensive direct measurement setup for longitudinal emittance serves to elucidate the impact of RFQ and buncher on the longitudinal phase space distribution within a medium-energy beam transport (MEBT) system.

I have read and accept the Privacy Policy Statement Yes

Primary author

Yong Zhang (Institute of Modern Physics, Chinese Academy of Sciences)

Co-authors

Ze Du (Institute of Modern Physics, Chinese Academy of Sciences) Lili Li (Institute of Modern Physics, Chinese Academy of Sciences) Jia Yin (Institute of Modern Physics, Chinese Academy of Sciences) Jianjun Su (Institute of Modern Physics, Chinese Academy of Sciences) Huan Jia (Institute of Modern Physics, Chinese Academy of Sciences) Yuanshuai Qin (Institute of Modern Physics, Chinese Academy of Sciences)

Presentation materials