Reevaluation of atomic bomb dose 1986 (DS86) -Radiation effect for atomic bomb survivors according to new dosimetry system-

1986年原子弹剂量重新评估（DS86） -根据新剂量测定系统对原子弹幸存者的辐射影响-

基本信息

批准号：
07458132
负责人：
HOSHI Masaharu
金额：
$ 3.65万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07458132/
关键词：
atomic bomb neutron DS86 radiation dose atomic bomb survivor's registry benchmark test gamma-ray dose Hiroshima

项目摘要

There are residual problems concerning DS86, therefore we proceed the study of the reevaluation of atomic bomb dose in Hiroshima and Nagasaki. We have been performed collaboration with some of the US groups. In 1996 we had workshop between US group and decided to begin a formal joint study. In 1997 we had workshop at RERF and discussed further studies.Problems are as follows : 1. We aagreed that there exists the systematic discrepancy between neutron induced data and calculation according to the former studies. We should note especially that the discrepancy over the distance of 1km is very large. 2. Therefore we should make intercomparison measurement among different groups. 3. To measure directly fast neutrons, we collect copper samples and measure neutron-induced nickel 63 as a result of copper n, p reaction. 4. In the case of Nagasaki data there are two contradicting data groups.One has the same systematic discrepancy as Hiroshima and the other has a good agreement with DS86. We mus … More t collect samples and make intercomparison between the two groups. 5. I proposed an assumption of leakage of bare fission neutrons from a crack which was produced when the botoom of the atomic bomb was came off. I had an answer from US group that it is not plausible, however they promised me to bring back and consider among the specialists, because there are not good possible process to solve neutron discrepancy in Hiroshima except this way. I also proposed the assumption to solve everything in Hiroshima.They are (1) there was 5% leakage of bare fission neutrons from the crack, (2) elevate 90m of the height of explosion and (3) increase 20% of the yield. The US group agreed the (3) from the different evidence. The neutron data more than 1km in Hiroshima is too large to explain from the transport calculation, therefore, we need to consider background problem of the measured data. We proceed the research study according to these discussions to have accurate dose evaluating system for atomic bomb survivors in Hiroshima and Nagasaki. Less

DS86还存在一些遗留问题，因此我们对广岛和长崎的原子弹剂量进行了重新评估。我们与一些美国团体进行了合作。1996年，我们与美国团体举行了研讨会，并决定开始正式的研究。 1997年我们在RERF召开了研讨会并讨论了进一步的研究。问题如下： 1.我们一致认为中子诱导数据和计算之间存在系统差异。根据以往的研究，我们要特别注意的是，在1km的距离上，差异很大。 2.因此，我们应该在不同组之间进行比较测量。 3.为了直接测量快中子，我们收集了铜样品并测量了中子。铜 n、p 反应导致镍 63 4。就长崎数据而言，存在两组相互矛盾的数据。一组与广岛具有相同的系统差异。与 DS86 非常一致。我们必须收集样本并在两组之间进行比较。 5. 我提出了原子弹底部脱落时产生的裂缝泄漏裸裂变中子的假设。我从美国小组得到的答复是这不太可信，但是他们答应我带回来并在专家中考虑，因为除了这种方式之外，没有很好的可能的过程来解决广岛的中子差异。我还提出了解决广岛所有问题的假设。它们是（1）裂变中子从裂缝中泄漏了5%，（2）爆炸高度提高了90m，（3）增加了20%的当量。美国小组从不同的证据中同意了(3)，广岛超过1km的中子数据太大，无法从输运计算中解释，因此，我们需要考虑测量数据的背景问题来进行研究。根据这些讨论进行研究，为广岛和长崎的原子弹幸存者建立准确的剂量评估系统。