Development of the modified sum-peak method and its application

As the sum-peak method requires the total count rate as well as the peak count rates and the sum peak count rate, this meets difficulties when a sample contains other radionuclides than the one to be measured. To solve the problem, a new method using solely the peak and the sum peak count rates was developed. The method was theoretically and experimentally confirmed using 60Co, 22Na and 134Cs. We demonstrate that the modified sum-peak method is quite simple and practical and is useful to measure multiple nuclides. •A modified sum-peak method for simple radioactivity measurement was developed.•The method solely requires the peak count rates and the sum peak count rate.•The method is applicable to multiple radionuclides.