硼中子捕獲治療(BNCT)為一種藉由中子引發10B(n,α)7Li核反應釋放之帶電粒子殺死癌細胞的標靶治療，這種治療方法成功的關鍵在於癌細胞對於含硼藥物的高吸收與高強度的超熱中子束。清華大學水池式反應器(THOR)為台灣唯一研究用反應器，於2004年將原先的中子射源改建為適合進行BNCT的超熱中子束，並於2010年進行第一例的臨床試驗。截至2020年1月已累積26例的臨床經驗與近100例的緊急治療計畫。現今平均一週便有ㄧ例以上的治療，因此可見THOR-BNCT設施在現今世界BNCT領域發展的重要性。
中子射束品質對於BNCT的穩定性相當重要，因此THOR-BNCT建立了例行的中子射束品保與品管(QA/QC)，分為雙游離腔及雙箔片活化兩部分，於BNCT照射前一天與治療當天早上進行中子射束強度與劑量的驗證。然而現行品保程序僅能確認中子射束強度，所能提供的能譜資訊相當有限，無法得到整體能量範圍的中子能譜資訊。
中子能譜量測傳統上使用金屬箔片做為活化偵檢器，或林姮孝學姊使用之改良活化偵檢器(球型活化偵檢器)，結合中子活化測量與MAXED，計算出中子能譜。然而上述兩種偵檢器ㄧ次只能照射一個偵檢器，需要相當多照射與量測時間。考慮到現今如此頻繁的治療日程，THOR-BNCT需要建立一套只須短時間的活化照射，同時能夠得到比雙箔片法更多能譜資訊之品保程序。
本研究設計之整合式中子能譜確認裝置，利用壓克力作為緩速體，改變活化箔片的照射位置，重新定義本裝置之初始能譜與偵檢器響應函數，能夠同時活化所有箔片(約30分鐘)，並將冷卻測量時間壓縮至一天之內，實驗隔天就能夠得到所有箔片量測結果及反解中子能譜，此外與傳統方法比較之下也能保有一定的準確度。本研究建議將此裝置加入THOR-BNCT的月或季的品保量測程序，強化對於中子射束能量分布資訊的掌握。

Boron neutron capture therapy (BNCT) is a targeted radiation cancer therapy based on the nuclear reaction 10B(n,α)7Li to kill tumor cells. Selectively concentrating boron compounds in tumor cells and intensive high-quality epithermal neutron beam are the keys to the success of this therapeutic modality. The Tsing Hua Open-Pool Reactor (THOR), a 2 MW research reactor at National Tsing Hua University (NTHU) in Taiwan, has been successfully upgraded and renovated for BNCT application in 2004. The first BNCT clinical trial using the THOR is carried out in 2010. Up to 2020, a total of 26 clinical trial and 100 emergency cases. Nowadays, BNCT treatment is at least one case a week, which indicates the high frequency of the THOR-BNCT neutron beam.
Since the quality of neutron source is crucial for the stability of BNCT therapy, measurements of dual ionization chambers and two bare activation foils which embedded in a phantom are irradiated at the beam port of THOR-BNCT are routinely performed as beam quality assurance/control procedures. This currently conducted procedure could only ensure the neutron source strength and efficiency of on line monitor system. To have more complete aspect of QA/QC, this study aims to develop a new method for neutron spectrum quality assurance procedure.
Conventiontal methods for neutron spectrum measurement in THOR-BNCT facility are bare activation foils and spherical-type activation detectors, combing with neutron activation analysis and maximum entropy unfolding algorithm. However, both of the detectors are activated one by one, which takes a lot of time. In the other hand, considering the impact beam scahdule of THOR-BNCT. The new method for spectrum quality assurance should take as less beam/measurement time as possible.
The new method is called integrated neutron spectrum confirming method. The response functions and initial spectrum are calculated by MCNP6 because the PMMA moderator and different places of activation foils. The activation foils are irradiated for 30 minutes in one time. Moreover, the time for cooling/measuring is less than 24 hours, which means that the spectrum quality assurance measurement can be done in one day with accuracy in certain level. Ultimately, this new device will be a part of quality assurance/control procedure and conducted quarterly or semiannualy.

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