快中子偵檢在輻射偵測的領域一直佔有一席之地，而由於快中子與物質作用的反應截面低，如何有效的量測也是近幾十年來追求的目標。其中有機閃爍偵檢器的使用，以及近二十年來複合式快中子有機偵檢器的發展，讓快中子得以更精準的被量測，而如今隨著電腦科技的進步，利用蒙地卡羅計算模擬中子偵檢器的工作過程，更強化了中子偵檢器開發的效率及結果預測。
要完整模擬閃爍偵檢器的工作過程，必須瞭解閃爍材料在輻射能量沉積時相對應的可見光子生成數量，然而這個部份的資料在Geant4中屬於使用者自訂義的資料庫，因此我們決定參考密西根大學於2015年發表的一款EJ-290與GS-20之複合式快中子閃爍偵檢器，針對其中的有機閃爍體EJ-290的光產率做校正。實驗中我們將EJ-290製備成2吋直徑2吋高的圓柱體，使用60鈷、137銫做為加馬射源，轟擊EJ-290獲得單位康卜吞電子能量沉積之光產率；再利用252鉲佐以中子飛行時間的技術獲得準單能量中子轟擊EJ-290獲得單位回跳質子能量沉積之光產率。校正結果電子能量沉積與光產率呈線性；質子能量沉積與光產率呈正相關但非線性，符合Birk’s Law的預期。

We would like to use the Monte Carlo simulation and refer to the idea of composite detector which is the combination of organic scintillator and inorganic scintillator to develop a high detection efficiency, high gamma/neutron discrimination capability fast neutron detectors. However, the data base of the Geant4 does not include the photon yield of scintillator material. Which means the simulation skips the step of photon yield and photon propagation. Leads to the simulation result may not be fully realistic.
We choose the organic scintillator EJ-290 refer to the paper published by Igor. Jovanovic, University of Michigan at 2015. The EJ-290 is fabricated as a 2 inches in diameter and 2 inches high cylinder. 60Co and 137Cs are taken to generate discrete energy gammas while 252Cf and the using of time of flight technique provide the quasi-monoenergetic neutrons for calibrating the photon yield. Both of the relation of Compton electron energy deposit between photon yield and the relation of recoil proton energy deposit between photon yield satisfy the Birk’s law.

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