# Development and Validation of a Digitizer-Based TCSPC System for Scintillation Decay Time Analysis via an Extended Convolution Model

## TL;DR

This paper introduces a new TCSPC system and model for accurately analyzing scintillator decay times, improving digital twin simulations.

## Contribution

A novel convolution model decouples scintillator effects from instrument response, enhancing decay time analysis accuracy.

## Key findings

- The extended convolution model improves decay time analysis by accounting for scintillator-induced timing effects.
- The model's accuracy was validated using both fast and slow scintillators.
- The system provides reliable parameterization for digital twin simulations of scintillation detectors.

## Abstract

The development of high-fidelity digital twins for scintillation spectrometer detectors demands precise experimental characterization of timing parameters. This work presents a comprehensive solution comprising a digitizer-based time-correlated single-photon counting (TCSPC) system and an extended convolution model for decay time analysis. We introduce a physics-driven calibration principle, validating the system response against an independent physical benchmark to ensure fidelity. The proposed convolution model advances beyond the conventional model by incorporating additional parameters to account for scintillator-induced timing broadening and delay, thereby decoupling this effect from instrumental response. The model’s descriptive power was statistically validated through its application to fast scintillators, while its physical accuracy was robustly confirmed through the precise extraction of typical decay times from slow scintillators. This methodology establishes a reliable workflow from measurement to parameterization, directly supplying the decoupled inputs required for the digital twins of scintillation detectors.