title: Focusing giga-electronvolt heavy ions to micrometers at the Institute of Modern Physics.
abstract: To study the radiation effect of cosmic heavy ions of low fluxes in electronics and living samples, a focusing heavy ion microbeam facility, for ions with energies of several MeV/u up to 100 MeV/u, was constructed in the Institute of Modern Physics of the Chinese Academy of Sciences. This facility has a vertical design and an experiment platform for both in-vacuum analysis and in-air irradiation. Recently, microbeam of (12)C(6+) with energy of 80.55 MeV/u was successfully achieved at this interdisciplinary microbeam facility with a full beam spot size of 3 μm × 5 μm on target in air. Different from ions with energy of several MeV/u, the very high ion energy of hundred MeV/u level induces problems in beam micro-collimation, online beam spot diagnosis, radiation protection, etc. This paper presents the microbeam setup, difficulties in microbeam formation, and the preliminary experiments performed with the facility.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, 509 Nanchang Rd., Lanzhou 730000, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Sheng
authors.forename: Guanghua
authors.initials: G
authors.lastname: Du
authors.forename: Jinlong
authors.initials: J
authors.lastname: Guo
authors.forename: Ruqun
authors.initials: R
authors.lastname: Wu
authors.forename: Mingtao
authors.initials: M
authors.lastname: Song
authors.forename: Youjin
authors.initials: Y
authors.lastname: Yuan
authors.forename: Guoqing
authors.initials: G
authors.lastname: Xiao