Photon reconstruction in calorimeters represents a crucial challenge in particle physics experiments, especially in high-density environments where shower overlapping probabilities become significant. We present an energy-core-based photon reconstruction method. It is achieved through extending the application of the Hough transform to exploit the energy-core structure of photon showers. The method, validated through simulations of the CEPC crystal electromagnetic calorimeter, achieves a reconstruction efficiency of nearly 100% for photons with energies exceeding 2 GeV and a separation efficiency approaching 100% for two 5 GeV photons, when the distance between them reaches the granularity limit of the calorimeter. This energy-core-based photon reconstruction method, integrated with an energy splitting technique, enhances the performance of photon measurement and provides a promising tool for imaging calorimeters, particularly those requiring high precision in photon detection in complex event topologies with high multiplicity.
@article{arxiv.2508.20728,
title = {Photon reconstruction using the Hough transform in imaging calorimeters},
author = {Yang Zhang and Shengsen Sun and Weizheng Song and Fangyi Guo and Yuanzhan Wang and Linghui Wu and Yifang Wang},
journal= {arXiv preprint arXiv:2508.20728},
year = {2026}
}