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arXiv · 1701.01790

The bunch current measurement using high-speed photodetector at HLS II

Tian-Yu Zhou·Yong-Liang Yang·Bao-Gen Sun·Ping Lu·Fang-Fang Wu·Ji-Gang Wang·Ze-Ran Zhou·Qing Luo·Qian Wang·Hao Li
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Abstract

This contribution presents a novel bunch current measurement system based on an ultra-fast photodetector and a high-speed digitizer at Hefei Light Source II (HLS II). In order to achieve bunch-by-bunch resolution, the sampling rate of the system is nearly 225 GS/s via a dedicated equivalent sampling algorithm. According to preliminary tests of daily operation mode and single-bunch mode, the root-mean-square (rms) of current relative error distribution is 1.03%, which illustrates the new system satisfies requirements for high-precision bunch current measurement. In addition, experiment results of "HLS" Morse code fill pattern mode demonstrate this system also could be a convenient and robust tool for beam top-up mode in the future.

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Tian-Yu Zhou, Yong-Liang Yang, Bao-Gen Sun, Ping Lu, Fang-Fang Wu, Ji-Gang Wang, Ze-Ran Zhou, Qing Luo, Qian Wang, Hao Li. 2017-01-07. The bunch current measurement using high-speed photodetector at HLS II. https://doi.org/10.1109/tns.2017.2713699

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