Reference dosimetry for light-ion beams based on graphite calorimetry.
Reference dosimetry for light-ion beams based on graphite calorimetry.
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基于石墨量热法的轻离子束参考剂量测定。
DOI：
10.1093/rpd/nct299
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发表时间：
2014
影响因子：
1
通讯作者：
S. Vynckier
中科院分区：
文献类型：
--
作者：
S. Rossomme;H. Palmans;R. Thomas;N. Lee;S. Duane;M. Bailey;D. Shipley;D. Bertrand;F. Romano;P. Cirrone;G. Cuttone;S. Vynckier
强子治疗的发展需要努力提高传递到目标体积的剂量的准确性。对参考条件下吸收剂量的测定进行了分析。根据国际原子能机构TRS-398实用守则，对于强子束，从电离室得出的参考条件下对水的吸收剂量的综合标准不确定度太大。这种不确定性主要是由光束质量校正因子决定的，[公式：见正文]，主要是由于在空气中产生一个离子对的平均能量，WAIR。减少这种不确定度的一种方法是使用量热法进行一次剂量测定。A[公式：请参阅文本]-值可以通过量热法和电离法之间的直接比较得出。在这里，这种比较是使用80 MeV A(-1)碳离子束中的石墨量热计进行的。假定推荐的水-石墨阻止功率比的TRS-398值和电离室的扰动因子，初步结果表明WAIR值为35.5±0.9 J C(-1)。
Developments in hadron therapy require efforts to improve the accuracy of the dose delivered to a target volume. Here, the determination of the absorbed dose under reference conditions was analysed. Based on the International Atomic Energy Agency TRS-398 code of practice, for hadron beams, the combined standard uncertainty on absorbed dose to water under reference conditions, derived from ionisation chambers, is too large. This uncertainty is dominated by the beam quality correction factors, [Formula: see text], mainly due to the mean energy to produce one ion pair in air, wair. A method to reduce this uncertainty is to carry out primary dosimetry, using calorimetry. A [Formula: see text]-value can be derived from a direct comparison between calorimetry and ionometry. Here, this comparison is performed using a graphite calorimeter in an 80-MeV A(-1) carbon ion beam. Assuming recommended TRS-398 values of water-to-graphite stopping power ratio and the perturbation factor for an ionisation chamber, preliminary results indicate a wair-value of 35.5 ± 0.9 J C(-1).