本研究旨在評估利用CR-39固態核軌跡底片在航空環境中測量宇宙輻射劑量的可行性。根據ICRP和NCRP報告，長期暴露於航空高度宇宙輻射的機組人員應視為職業性暴露對象，需控制其年度劑量。本研究使用THOR-BNCT、Cf-252快中子和Co-60伽馬射線等輻射源，以及MCNP和NTHU Flight Dose Calculator模擬軟體進行評估。
實驗結果顯示，延長化學蝕刻時間會增加CR-39底片收集的核軌跡數量和孔徑大小，但過長的時間將導致過度蝕刻。存儲條件實驗顯示，低溫保存效果最佳，但14天內室溫保存的核軌跡數與對照組相近。CR-39底片對低LET輻射不敏感，機載量測時主要偵測宇宙輻射中的質子以及中子的帶電回跳粒子。本研究利用Fiji軟體自動計數，達到最佳效率，光學掃描確保最大視野，減少訊號損失。
不同輻射場的劑量轉換因子存在顯著差異，底片靈敏度會隨中子能量增加而降低，因此快中子校正場所得劑量-核軌跡數轉換因子比BNCT治療室較低。實際飛航測量顯示，除了第一條路線因飛行高度較低，航線較短，偏差較大，其餘航線呈現良好一致性，顯示CR-39底片在飛行劑量偵測方面具有良好的性能顯示底片的可靠性。綜合結果，本研究證實了CR-39底片在航空環境中測量輻射劑量是可行的，並透過不同輻射場驗證其在輻射劑量監測中的準確性和可靠性。未來計劃使用雙劑量偵檢器交叉驗證，並繼續收集新飛航路線數據，以提高轉換因子精確度，實際量測國內機組人員之劑量。

This study evaluates the feasibility of using CR-39 plastic nuclear track detectors (PNTDs) to measure cosmic radiation doses in aviation. Aircrew exposed to cosmic radiation should be considered occupationally exposed according to ICRP and NCRP guidelines. We used radiation sources such as THOR-BNCT, Cf-252 fast neutrons, and Co-60 gamma rays, along with MCNP and NTHU Flight Dose Calculator simulations.
Experimental results showed that extended chemical etching increases track numbers but can lead to over-etching. Low-temperature storage was most effective, but 14 days at room temperature showed similar results. CR-39 detectors are primarily sensitive to protons and neutron recoil particles. Automated counting with Fiji software and optical scanning ensured efficiency and minimized signal loss.
Dose conversion factors varied significantly between radiation fields, with CR-39 sensitivity decreasing as neutron energy increased. Flight measurements showed consistent results across most routes, confirming the reliability of CR-39 detectors for in-flight dose measurement.
Overall, CR-39 PNTDs are feasible for measuring radiation doses in aviation, with plans for further validation and data collection to improve accuracy for domestic aircrew dosimetry.

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