Study on the Dependence of Energy Resolution on Reflector Material for Inorganic Crystal Scintillators Using the Geant4

Abstract

The scintillator has played a primary role as the ideal device for the detection and measurement of particles and radiation in modern physics. With the development of experimental physics, the demand for new improved scintillating materials for several types of applications has kept increasing. High efficiency, fast scintillation and good energy resolution are among the most desired specifications as to a good scintillator. Yet, a variety of scintillators can be preferred depending on the precise specifications of the application considered. If the case is that the detection of gamma rays and high-energy electrons or positrons, inorganic crystals are exceptionally suitable scintillator because highly intense light outputs and the strong stopping power enable these type of crystals to provide better energy resolution among all scintillators. In this study, a scintillation detector consisting of inorganic crystal scintillator material (NaI:Tl and CsI:Tl) was modeled with the help of Geant4 scientific toolkit to determine if the energy resolution of the inorganic crystal scintillator detector is dependent on crystalline size and reflector material. In each simulation, different sized crystal covered with a variety of reflector type was exposed to the same energy gamma radiation; the resulting energy spectrum was evaluated and compared to others obtained.

Keywords

• Scintillation Detector
• Inorganic Crystal
• Reflector Material
• Geant4

Geant4 ile İnorganik Kristal Sintilatörler için Enerji Çözünürlüğünün Reflektör Malzemesine Bağımlılığı Üzerine Çalışma

Abstract

Sintilatör, modern fizikte parçacıkların ve radyasyonun saptanması ve ölçülmesi için ideal bir cihaz olarak birincil bir rol oynamıştır. Deneysel fiziğin gelişmesiyle birlikte, çeşitli uygulama türleri için yeni geliştirilmiş parıldayan malzemelere olan talep artmaya devam etti. İyi bir sintilatör için yüksek verimlilik, hızlı parıldama ve iyi enerji çözünürlüğü en çok istenen özellikler arasındadır. Yine de, dikkate alınan uygulamanın kesin özelliklerine bağlı olarak çeşitli sintilatörler tercih edilebilir. Durum, gama ışınlarının ve yüksek enerjili elektronların veya pozitronların tespiti ise, inorganik kristaller son derece uygun sintilatördür çünkü yüksek yoğunluklu ışık çıkışları ve güçlü durdurma gücü, bu tür kristallerin tüm sintilatörler arasında daha iyi enerji çözünürlüğü sağlamasını sağlar. Bu çalışmada, inorganik kristal sintilatör dedektörünün enerji çözünürlüğünün kristal boyutuna bağlı olup olmadığını belirlemek için inorganik kristal sintilatör materyalinden (NaI:Tl ve CsI:Tl) oluşan bir sintilasyon dedektörü Geant4 bilimsel araç kiti yardımıyla modellenmiştir. Her simülasyonda, çeşitli reflektör tipi ile kaplanmış farklı büyüklükteki kristal aynı enerji gama radyasyonuna maruz bırakılmış, elde edilen enerji spektrumu değerlendirilmiş ve elde edilen diğerleriyle karşılaştırılmıştır.

Keywords

• Sintilasyon Dedektörü
• İnorganik Kristal
• Reflektör Materyal
• Geant4

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