The response of thermally and optically stimulated luminescence from Al₂O₃:C to high-energy heavy charged particles

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• 作者：Gaza ; R. ; Yukihara ; E.G. ; McKeever ; S.W.S.
• 关键词：Optically stimulated luminescence ; Thermoluminescence ; Aluminum oxide ; Heavy charged particle
• 刊名：Radiation Measurements
• 出版年：2004
• 出版时间：August - December, 2004
• 年：2004
• 卷：38
• 期：4-6
• 页码：417-420
• 全文大小：262 K

文摘

The thermoluminescence (TL) and optically stimulated luminescence (OSL) response of Al₂O₃ dosimeters to high-energy heavy charged particles (HCP) has been studied using the heavy ion medical accelarator at Chiba, Japan. The samples were Al₂O₃ single-crystal chips, of the type usually known as TLD-500, and Luxel^TM dosimeters (Al₂O₃:C powder in plastic) from Landauer Inc. The samples were exposed to ⁴He (150MeV/u), ¹²C (400MeV/u), ²⁸Si (490MeV/u) and ⁵⁶Fe (500MeV/u) ions, with linear energy transfer values covering the range from 2.26 to 189keV/μm in water and doses from 1 to 100mGy (to water). A ⁹⁰Sr/⁹⁰Y beta source, calibrated against a ⁶⁰Co secondary standard, was used for calibration purposes. For OSL, we used both continuous-wave OSL measurements (CW-OSL, using green light stimulation at 525nm) and pulsed OSL measurements (POSL, using 532nm stimulation from a Nd:YAG Q-switched laser). The efficiencies (η_HCP,γ) of the different HCPs at producing OSL or TL were observed to depend not only upon the linear energy transfer (LET) of the HCP, but also upon the sample type (single crystal chip or Luxel^TM) and the luminescence method used to define the signal—i.e. TL, CW-OSL initial intensity, CW-OSL total area, or POSL. Observed changes in shape of the decay curve lead to potential methods for extracting LET information of unknown radiation fields. A discussion of the results is given, including the potential use of OSL from Al₂O₃ in the areas of space radiation dosimetry and radiation oncology.