The neutron production in ASDEX Upgrade (AUG) neutral beam injection (NBI) heated discharges is dominated by beam-target fusion reactions. Hence, the neutron rate (NR) and energy distributions are footprints of the fast ion distribution. This motivates to establish a reliable neutron rate calibration. Comparisons at AUG between the experimental NR and the one predicted by the TRANSP code show systematic variations from campaign to campaign. Potential reason for this is the delicate absolute calibration of the neutron detectors. Therefore, a different calibration technique was performed, enabling longer acquisition time, uniform geometry, better statistics and thus less uncertainty. A toy train carrying a radioactive source (${}^{238}$Pu/B) over two radial positions on the equatorial plane shows a periodical NR on the epithermal ${}^3$He neutron detector. The calibration results are compared to a neutron transport simulation using the Monte Carlo (MC) code Serpent. Preliminary comparisons for one source position on the outer railway track show a discrepancy factor of about 130 in the position of least material inside the simulation, in the direct line of sight to the detector. For a better understanding of these results, two additional measurements were performed. The results were again compared to a detailed Serpent simulation. This paper describes the calibration set-up for the neutron measurements in AUG, provides a brief simulation background on reaction rate estimations and a survey on the comparison between the measured and calculated neutron rates.

ASDEX 升级 (AUG) 中性束注入 (NBI) 加热放电中的中子产生主要由束靶聚变反应控制。因此，中子速率 (NR) 和能量分布是快离子分布的足迹。这促使建立可靠的中子率校准。8 月的实验 NR 与 TRANSP 代码预测的 NR 之间的比较显示了不同活动之间的系统变化。造成这种情况的潜在原因是中子探测器的精密绝对校准。因此，执行了不同的校准技术，从而实现更长的采集时间、统一的几何形状、更好的统计数据，从而减少不确定性。载有放射源的玩具火车（${}^{238}$Pu/B) 在赤道平面上的两个径向位置上显示了超热液上的周期性 NR ${}^3$他中子探测器。校准结果与使用蒙特卡罗 (MC) 代码 Serpent 的中子传输模拟进行比较。对外部铁路轨道上一个源位置的初步比较显示，在模拟内部材料最少的位置，在检测器的直接视线中，差异因子约为 130。为了更好地理解这些结果，进行了两次额外的测量。结果再次与详细的 Serpent 模拟进行比较。本文描述了 AUG 中子测量的校准设置，提供了关于反应速率估计的简要模拟背景，以及对测量和计算中子速率之间比较的调查。