Optimization of Scintillation Light Collection Efficiency in BGO Crystals With Surface Diffusion for Enhanced Sensitivity in the KAPAE

Optimization of Scintillation Light Collection Efficiency in BGO Crystals With Surface Diffusion for Enhanced Sensitivity in the KAPAE Научная публикация

Журнал

IEEE Transactions on Nuclear Science
ISSN: 0018-9499 , E-ISSN: 1558-1578

Вых. Данные

Год: 2025, Том: 72, Номер: 7, Страницы: 2071 - 2075 Страниц : 5 DOI: 10.1109/TNS.2025.3552904

Авторы

Jeong D.W. ¹ , Choi E. ¹ , Cho J.Y. ¹ , Luan N.T. ¹ , Park H. ¹ , Park H.W. ² , Shlegel V. ³ , Kim H.J. ¹

Организации

1	Department of Physics, Kyungpook National University, Daegu, South Korea
2	Korea Research Institute of Standards and Science (KRISS), Daejeon, South Korea
3	Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, Novosibirsk, Russia

The Kyungpook National University (KNU) Advanced Positronium Annihilation Experiment (KAPAE) aims to search for rare decays of positronium. The Phase I detector of KAPAE, equipped with Bismuth Germanate (Bi4Ge3O12, BGO) scintillation crystals with a polished surface, was designed to observe rare visible decays. The BGO scintillation crystals were chosen for their high gamma detection efficiency, high density, and high effective atomic number, making them suitable for gamma-ray detection in various applications, including medical imaging and high-energy physics experiments. However, due to its high refractive index of 2.15, BGO experiences considerable internal light trapping, which significantly reduces the efficiency of scintillation light collection. The Phase II detector focuses on detecting invisible decays of positronium by improving light collection efficiency and energy resolution while minimizing dead areas using surface-diffused BGO crystals. This paper investigates the light collection efficiency of 3 × 3 × 15 cm3 surface-diffused BGO crystals, demonstrating an approximately 22% higher light yield compared to polished surfaces. This improvement is confirmed by Monte Carlo simulations using the Geant4 toolkit, which predict similar enhancements in light collection efficiency. The energy resolution is improved from an average of 12% to 10.8% with the diffused BGO crystals at 662 keV. These results enhance the sensitivity of the KAPAE Phase II detector to invisible decays of positronium. These improvements in light collection efficiency and energy resolution of surfacediffused BGO crystals make them suitable materials for broader applications in experiments that require precise gamma energy measurement. In this paper, we present the optimization of the KAPAE detector, providing insights for the design and enhancement of scintillation detector performance in particle physics and other high-energy applications.

Jeong D.W. , Choi E. , Cho J.Y. , Luan N.T. , Park H. , Park H.W. , Shlegel V. , Kim H.J.
Optimization of Scintillation Light Collection Efficiency in BGO Crystals With Surface Diffusion for Enhanced Sensitivity in the KAPAE
IEEE Transactions on Nuclear Science. 2025. V.72. N7. P.2071 - 2075. DOI: 10.1109/TNS.2025.3552904 Scopus

Опубликована в печати:

19 мар. 2025 г.

Scopus:

2-s2.0-105001041603

Пока нет цитирований