rteü-femüd Recep Tayyip Erdogan University Journal of Science and Engineering 2687-2315 2757-7686 Recep Tayyip Erdoğan Üniversitesi 10.53501/rteufemud.1709235 Nuclear Physics Radiation Technology Nükleer Fizik Radyasyon Teknolojisi Impact of Surface Coating Materials and Geometry on the Efficiency of Organic and Inorganic Scintillators: A GEANT4 Simulation Study Yüzey Kaplama Malzemeleri ve Geometrisinin Organik ve İnorganik Sintilatörlerin Verimliliği Üzerindeki Etkisi: Bir GEANT4 Simülasyon Çalışması https://orcid.org/0000-0002-7670-7112 Emirhan Mehmet Erhan ISTANBUL UNIVERSITY, FACULTY OF SCIENCE 06 30 2025 6 1 330 343 05 29 2025 06 10 2025 Copyright © 2020, Recep Tayyip Erdoğan Üniversitesi Fen ve Mühendislik Bilimleri Dergisi 2020 Recep Tayyip Erdoğan Üniversitesi Fen ve Mühendislik Bilimleri Dergisi

This study investigates the impact of various reflective coating materials on the photon counting efficiency of selected organic and inorganic scintillators using GEANT4 simulation toolkit. Reflective coatings, including titanium dioxide, TeflonTM tape and aluminum foil, were applied to both scintillator surfaces to analyse photon collection efficiency by counting optical photons. The simulations were conducted for gamma photon energies of 59 keV, 662 keV and 1173 keV representative of low, medium, and high-energy regimes. The results indicate that aluminum foil provides the highest photon collection efficiency for high-energy gamma photons, while teflon tape exhibits superior performance at lower energies. Multilayer coatings of titanium dioxide and teflon tape show incremental improvements in photon collection, whereas aluminum foil achieves high reflectivity with a single layer, making it a cost-effective and efficient solution. Furthermore, the efficiency enhancement is significantly more pronounced in organic scintillators. These findings provide valuable insights into the selection of optimal reflective coatings for different scintillator materials and radiation energy levels, contributing to the optimization of radiation detection systems used in medical imaging, nuclear physics, and high-energy particle experiments.

Bu çalışma, GEANT4 simülasyon araç setini kullanarak çeşitli yansıtıcı kaplama malzemelerinin seçili organik ve inorganik sintilatörlerin foton sayım verimliliği üzerindeki etkisini araştırmaktadır. Titanyum dioksit, TeflonTM bant ve alüminyum folyo dahil yansıtıcı kaplamalar, optik fotonları sayarak foton toplama verimliliğini analiz etmek için her iki sintilatör yüzeyine uygulanmıştır. Simülasyonlar, düşük, orta ve yüksek enerjili rejimleri temsil eden 59 keV, 662 keV ve 1173 keV gama foton enerjileri için oluşturulmuştur. Sonuçlar, alüminyum folyonun yüksek enerjili gama fotonları için en yüksek foton toplama verimliliğini sağladığını, TeflonTM bandın ise daha düşük enerjilerde üstün performans gösterdiğini göstermektedir. Titanyum dioksit ve TeflonTM banttan oluşan çok katmanlı kaplamalar, foton toplamada kademeli iyileştirmeler gösterirken, alüminyum folyo tek bir katmanla yüksek yansıtma özelliğine ulaşarak maliyet açısından etkili ve verimli bir çözüm haline gelmektedir. Ayrıca, verimlilik artışı organik sintilatörlerde önemli ölçüde daha belirgin bulunmuştur. Bu bulgular, farklı sintilatör malzemeleri ve radyasyon enerji seviyeleri için optimum yansıtıcı kaplamaların seçimi konusunda değerli bilgiler sağlayarak, tıbbi görüntüleme, nükleer fizik ve yüksek enerjili parçacık deneylerinde kullanılan radyasyon tespit sistemlerinin optimizasyonuna katkıda sağlamaktadır.

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