title: A 128-channel picoammeter system and its application on charged particle beam current distribution measurements.
abstract: A 128-channel picoammeter system is constructed based on instrumentation amplifiers. Taking advantage of a high electric potential and narrow bandwidth in DC energetic charged beam measurements, a current resolution better than 5 fA can be achieved. Two sets of 128-channel strip electrodes are implemented on printed circuit boards and are employed for ion and electron beam current distribution measurements. Tests with 60 keV O(3+) ions and 2 keV electrons show that it can provide exact boundaries when a positive charged particle beam current distribution is measured.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Deyang
authors.initials: D
authors.lastname: Yu
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Junliang
authors.initials: J
authors.lastname: Liu
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Yingli
authors.initials: Y
authors.lastname: Xue
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Mingwu
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Cai
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Hu
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Jinmei
authors.initials: J
authors.lastname: Dong
authors.affiliation: School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li