厚いアクリル樹脂製のトリチウム線源で観測されたX線スペクトルの解析及びシミュレーション

概要

論文の詳細を見る
The b-ray-induced X-ray spectra observed for a polymer disk (1 mm thickness), which was made of poly-methylmethacrylate labeled with tritium, were analyzed and they were reproduced by computer simulation based on the uniform distribution of tritium in the polymer disk. The X-ray spectra were measured in both helium and argon atmospheres. An X-ray spectrum observed in the helium atmosphere consisted of only a broad bremsstrahlung X-ray peak, while in the argon atmosphere a characteristic X-ray peak appeared in addition to bremsstrahlung X-rays. From differences in the shape and intensity of X-ray spectra observed in both atmospheres, the conversion fraction of the bremsstrahlung X-rays to the characteristic X-rays in an argon atmosphere was determined to be 7.1x10-2 by taking the absorption coefficient of X-rays into account. The spectra observed in both atmospheres could be reproduced quite well by using the equations to estimate generation and attenuation of X-rays in various materials. It was suggested, therefore, that a tritium depth profile in carbonaceous materials can be evaluated by the numerical simulation. Furthermore, the simulation indicated that nitrogen could be also used as a promising alternative gas of helium for evaluation of a tritium depth profile in bulk.