Towards real-time digital pulse processing based on least-mean-squares algorithms

The high potential of digital least-mean-squares methods in high-resolution nuclear spectroscopy cannot be fully exploited at present due to its heavy calculation burden which makes difficult a real-time implementation. A method for reducing the mathematical complexity of least-mean-squares algorithms used for deriving energy and arrival time of detected events, is presented here. It yields an easier path toward real-time implementation. The availability of the time information of each event allows the realisation of a statistical digital pile-up rejector based on the values of a Chi-square distribution associated to the measurement algorithm: this rejector is very sensitive to piled-up low-energy events.