Abstract The intensity of keV positron beam generated by 22Na slow positron beam device is weak (generally less than 106 e+/s). Therefore, the traditional method of obtaining beam intensity by Faraday cup is no longer applicable. Currently published methods of obtaining beam intensity are relatively deficient and insufficient. In this paper, a new method was developed to obtain the real-time intensity of positron beam, that is, the HPGe detector was used to collect the 511-keV photons emitted from the thick target bombarded by the positrons, combining with the experimental calibration value of HPGe detector for 511-keV photons as a22Na standard point source placed at the collision point of thick carbon target, and with the relevant parameters got by Monte Carlo simulation. Moreover, the method our group developed and the corrected method of others were both applied for online measurement of beam intensity of 4–9 keV positrons colliding with the pure thick targets (Al, Zn, Nb and Pb). Through comparative analyses, the method our group developed could measure positron beam intensity online more accurately.

中文翻译：

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keV正电子束强度在线测量

摘要 22Na慢正电子束装置产生的keV正电子束强度较弱（一般小于106 e+/s）。因此，传统的法拉第杯获取光束强度的方法已不再适用。目前公开的获得光束强度的方法相对不足和不足。本文提出了一种实时获取正电子束强度的新方法，即利用HPGe探测器采集正电子轰击厚靶所发射的511 keV光子，并结合实验标定。 511-keV 光子作为 22Na 标准点源放置在厚碳靶的碰撞点的 HPGe 探测器的值，以及蒙特卡罗模拟得到的相关参数。而且，我们小组开发的方法和其他人的校正方法都应用于在线测量与纯厚靶（Al、Zn、Nb 和 Pb）碰撞的 4-9 keV 正电子的光束强度。通过对比分析，我们小组开发的方法可以更准确地在线测量正电子束强度。