Radiation tolerance of readout electronics for Belle II
Radiation tolerance of readout electronics for Belle II
复制标题
Belle II 读出电子设备的辐射耐受性
DOI：
10.1088/1748-0221/7/02/c02022
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发表时间：
2011
影响因子：
1.3
通讯作者：
and E. Nakano
中科院分区：
文献类型：
--
作者：
T. Higuchi;M. Nakao;and E. Nakano
我们计划于 2015 年开始 Belle II 实验，并持续收集数据十多年。由于Belle II的一些前端电子卡位于探测器内部，对其组件的辐射影响将是一个严重的问题。我们使用中子和 γ 射线实验暴露设施，研究这些粒子对 Virtex-5 FPGA、光收发器和电压调节器的辐射效应。研究发现，Virtex-5 FPGA 在受到 Belle II 20 年以上等效中子通量和 88 年等效 γ 射线剂量照射后仍能保持运行。我们在中子辐照下的 Virtex-5 FPGA 中观察到单粒子翻转 (SEU) 和多位翻转 (MBU)。我们还发现 Virtex-5 FPGA 中从尾侧轰击的 SEU 数量几乎是从头侧轰击的数量的两倍。我们将 Virtex-5 FPGA 中观察到的 SEU 和 MBU 计数外推到 Belle II 中央漂移室的整个读出系统，并预计 SEU 和 MBU 速率分别为每 4 分钟 1 个 SEU 和每 11.5 小时 1 个 MBU。研究发现，光收发器在积分12年当量中子通量后仍能保持运行，而在约3年当量的γ射线剂量下会被杀死，这应该在未来的研究中解决。研究发现，电压调节器在 10 年以上的当量 γ 射线剂量下仍能保持运行。
We plan to start the Belle II experiment in 2015 and to continue data taking for more than ten years. Because some of the front-end electronics cards of Belle II are located inside the detector, radiation effects onto their components will be a severe problem. Using experimental exposure facilities of neutrons and γ rays, we study the radiation effects from these particles to the Virtex-5 FPGA, optical transceivers, and voltage regulators. The Virtex-5 FPGA is found to keep its operation after irradiation of more than 20-year-equivalent neutron flux of Belle II and 88-year-equivalent γ-ray dose. We observe single event upsets (SEUs) and multiple bit upsets (MBUs) in the Virtex-5 FPGA in the neutron irradiation. We also find almost doubled SEU counts in the Virtex-5 FPGA bombarded from its tail side than its head side. We extrapolate the observed SEU and MBU counts in the Virtex-5 FPGA to the entire readout system of the Belle II central drift chamber, and expect the SEU and MBU rates as one SEU per four minutes and one MBU per 11.5 hours, respectively. The optical transceivers are found to keep its operation after integration of 12-year-equivalent neutron flux, while they are killed by about 3-year-equivalent γ-ray dose, which should be solved in the future research. The voltage regulators are found to keep its operation for more than 10-year-equivalent γ-ray dose.