Ruckerbauer F, Sprunck M, Regulla D F
GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Strahlenschutz, Oberschleissheim, Germany.
Appl Radiat Isot. 1996 Nov-Dec;47(11-12):1263-8. doi: 10.1016/s0969-8043(96)00161-3.
Electron spin resonance (ESR) spectra of alanine detectors irradiated to absorbed doses below 5 Gy are affected by a varying non-linear background which mainly influences the lower limit of detection in alanine/ESR dosimetry. A mathematical method based on fast Fourier transform is described capable of filtering simultaneously background and noise in the frequency domain of ESR spectra. It provides clearer alanine/ESR signals down to 50 mGy. Even in non-irradiated but long-term stored alanine detectors an ESR signal could be observed similar to irradiated alanine (pre-signal). A linear ESR signal vs absorbed dose relationship was found above 200 mGy, after correction for background and pre-signal. The number of repeated ESR read-out cycles and hence the time required for a precise and reliable low-dose evaluation have significantly been reduced. The method has been worked out for the therapy-level dosimetry range and tested on a Bruker ESP 300 and for comparison Bruker EMS 104 ESR spectrometer.
辐照吸收剂量低于5 Gy的丙氨酸探测器的电子自旋共振（ESR）光谱受变化的非线性本底影响，该本底主要影响丙氨酸/ESR剂量测定中的检测下限。描述了一种基于快速傅里叶变换的数学方法，该方法能够在ESR光谱的频域中同时滤除本底和噪声。它能提供低至50 mGy的更清晰的丙氨酸/ESR信号。即使在未辐照但长期储存的丙氨酸探测器中，也能观察到与辐照丙氨酸类似的ESR信号（预信号）。在校正本底和预信号后，发现高于200 mGy时ESR信号与吸收剂量呈线性关系。重复ESR读出循环的次数以及因此进行精确可靠的低剂量评估所需的时间已显著减少。该方法已针对治疗级剂量测定范围进行了开发，并在布鲁克ESP 300以及用于比较的布鲁克EMS 104 ESR光谱仪上进行了测试。
