A Crack Model of the Hiroshima Atomic Bomb: Explanation of the Contradiction of "Dosimetry System 1986"

URI http://harp.lib.hiroshima-u.ac.jp/hbg/metadata/5696
ファイル
タイトル
A Crack Model of the Hiroshima Atomic Bomb: Explanation of the Contradiction of "Dosimetry System 1986"
著者
氏名 岡 隆光
ヨミ オカ タカミツ
別名 Oka Takamitsu
氏名
ヨミ エンドウ サトル
別名 Endo Satoru
氏名
ヨミ タカダ ジュン
別名 Takada Jun
氏名
ヨミ イシカワ マサヨリ
別名 Ishikawa Masayori
氏名
ヨミ ニッタ ユミコ
別名 Nitta Yumiko
氏名
ヨミ イワタニ カズオ
別名 Iwatani Kazuo
氏名 星 正治
ヨミ ホシ マサハル
別名 Hoshi Masaharu
氏名
ヨミ フジタ ショウイチロウ
別名 Fujita Shoichiro
氏名 静間 清
ヨミ シズマ キヨシ
別名 Shizuma Kiyoshi
氏名 葉佐井 博巳
ヨミ ハサイ ヒロミ
別名 Hasai Hiromi
キーワード
Crack model
Hiroshima atomic bomb
Neutrorl!Neutron discrepancy
DS86
抄録

There has been a large discrepancy between the Dosimetry system 1986 (DS86) 'and measured data, some of which data in Hiroshima at about 1.5 km ground distance from the hypocenter are about 10 times larger than the calculation. Therefore its causes have long been discussed , since it will change the estimated radiation risks obtained based on the Hiroshima and Nagasaki data. In this study the contradiction was explained by a bare-fission-neutron leakage model through a crack formed at the time of neutron emission. According to the present calculation, the crack has a 3 cm parallel spacing, which is symmetric with respect to the polar axis from the hypocenter to the epicenter of the atomic bomb. We made also an asymmetric opening closing 3/4 0f this symmetric geometry, because there are some data which shows asymmetry '' . In addition, the height of the neutron emission point was elevated 90 m. By using the asymmetric calculation, especially for long distant data located more than 1 km, it was verified that all of the activity data induced by thermal and fast neutrons, were simultaneously explained within the data scattering. The neutron kerma at a typical 1.5 km ground distance increases 3 and 8 times more than DS86 based on the symmetric and asymmetric model, respectively.

掲載雑誌名
Journal of radiation research
40
Suppl
開始ページ
145
終了ページ
154
出版年月日
1999-12
出版者
日本放射線影響学会
本文言語
英語
資料タイプ
学術雑誌論文
著者版フラグ
旧URI
区分
hbg