Implementation and verification of real- time nuclear signal pile-up and separation algorithm based on FPGA

In high count-rate environments, the problem of nuclear signal pile-up can affect the analysis of subsequent results, so it is necessary to process the pile-up signal. The commonly used solution currently is to use pile-up recognition to reject, but this method can cause loss of counts and has limitations in some applications such as timing analysis.

[Purpose] This study proposes a real-time pile-up separation algorithm that performs fast/slow shaping processing on the original signal. [Methods] Fast shaping used the triangular shaping method to obtain the arrival time of the nuclear signal to determine whether pile-up occurred; Slow shaping adopted the trapezoidal shaping method to extract the energy information of the nuclear signal. At the same time, by using the symmetrical rising/falling edge features of the trapezoidal signals, the pile-up signal was separated according to the time point of pile-up occurrence to improve the counting performance of the system.