Decaying source model: Alternative approach to determination of true counting rates at X and gamma ray counting systems

• A new approach for correction of the dead time caused by the counting system has been proposed.
• The dead time caused by the counting system electronics were taken into account.
• The proposed model was seen to provide an effective correction in counting rates with fluctuations.
• Simulation and experimental study next to the proposed theoretical model were performed.
• Theoretical and simulation results showed good agreement.

The counting systems consisting of electronic devices are used for detection of radiation due to X or gamma rays. The dead time of the counting system is based on time limitations of these electronic devices. The dead time causes counting losses. Determination of counting rate losses in quantitative and qualitative analysis become a vital step for correction of analysis. Therefore, compensating for counting rate losses is of great importance. These counting rate losses are due to piled up reject time, paralyzable or non-paralyzable system dead time or a combination of these mechanisms. Paralyzable and non-paralyzable models are well-known and frequently used for correction of counting rate losses dependent on the system dead time. However, these two models do not provide enough correction at medium and high counting rates. Therefore, the new models for corrections of counting rate losses are needed. For this reason, both an alternative approach is proposed and a simulation program is coded for counting rate losses in this study. A good agreement is obtained between theoretical model and simulation program.