In gamma-ray spectroscopy, a pulse pile-up occurs when a gamma-ray hits the detector within a time period shorter than the duration of the pulse induced by a preceding gamma-ray. The resulting pulse is the sum of two overlapping pulses. At a high counting rate, the pulse pile-up can lead to significant loss of data and/or deterioration of the measured gamma-ray energy spectrum. If the temporal separation of consecutive gamma-ray events is small enough, the resulting pile-up pulse exhibits only a single peak. Such events are described as peak pile-ups. It is not trivial to detect and correct peak pile-ups. Consequently, such events are typically wrongly reconstructed as a single pulse or rejected by the pile-up correction algorithms developed to date. We study a least-squares fitting algorithm modified to include detection and correction of peak pile-ups. Performance of the proposed algorithm is studied using data measured with LaBr${}_3$:Ce scintillator and a 400 MBq ¹³⁷Cs source as well as with artificially synthesized pile-up data. The pile-up correction success rate grows rapidly with the temporal separation of piled-up pulses and reaches 50% as soon as the pulses are separated by a time at least of the order of the single pulse rise time. A success rate exceeding 90% is reached for the temporal separation equal to about twice the rise time. The reconstruction efficiency measured as the overall rate of the successful reconstruction of the double-pulse pile-up is about 92%.

在伽马射线光谱学中，当伽马射线在比由先前的伽马射线引起的脉冲的持续时间短的时间段内撞击检测器时，发生脉冲堆积。产生的脉冲是两个重叠脉冲的总和。在高计数率下，脉冲堆积会导致数据大量丢失和/或所测得的伽马射线能谱变差。如果连续的伽马射线事件的时间间隔足够小，则产生的堆积脉冲仅显示一个峰值。这种事件被描述为高峰堆积。检测和纠正峰值堆积并非易事。因此，此类事件通常被错误地重建为单个脉冲，或者被迄今为止开发的堆积校正算法所拒绝。我们研究了一种最小二乘拟合算法，该算法经过修改以包括峰值堆积的检测和校正。使用LaBr测量的数据研究了该算法的性能${}_3$：Ce闪烁体和400 MBq ¹³⁷ Cs源以及人工合成的堆积数据。堆积校正成功率随着堆积脉冲的时间分离而迅速增长，并且一旦脉冲分离了至少单个脉冲上升时间量级的时间，则堆积校正成功率达到50％。时间间隔的成功率超过90％，大约等于上升时间的两倍。以成功重建双脉冲堆积的总速率衡量的重建效率约为92％。