- 著者
- Shichijo Kazuko Takatsuji Toshihiro Yamamoto Masayoshi Nakashima Masahiro
- 出版者
- 広島大学平和科学研究センター
- 雑誌
- IPSHU English Research Report Series
- 巻号頁・発行日
- no.28, pp.70-73, 2012-03
The explosion of a plutonium Atomic bomb over Nagasaki city in Japan took place at 1102h on August 9, 1945. Radiation dose of A-bomb survivor is practically estimated from external radiation. The alpha particles can be disregarded science they travel only a short distance through air. Plutonium remaining in the soil at Nagasaki after 24yr has been determined in 1971. In the patients subjected to the Atomic bomb there was no evidence of the introduction of radioactive material. We have already studied the preserved body cells of seven A-bombed victims in 1945, and became the first one to prove that plutonium is continuing to emit radiations after more than 60 years since the A-bomb attack. In this study, the nuclide identification of alpha-emitters in environmental samples and calibration standards has been attempted by the measurement of the alpha track length using autoradiography. Alpha track length in Nagasaki soil; Ground surface soil collected in 1979 from the Nishiyama area in Nagasaki City, 210Po, 241Am and 243Am fitted the relation curve between energy and track length of alpha-particles in the photo emulsion. Moreover, the alpha track length in Nagasaki soil was consisted with that in paraffin-embedded specimen of A-bomb cases. Therefore, the nuclide of alpha-emitters in specimen of atomic victims at Nagasaki was identified with 239,240Pu by autoradiography.
- 著者
- TAKADA JUN HOSHI MASAHARU NAGATOMO TSUNETO YAMAMOTO MASAYOSHI ENDO SATORU TAKATSUJI TOSHIHIRO YOSHIKAWA ISAO GUSEV BORIS I. SAKERBAEV ALEXANDER K. TCHAIJUNUSOVA NAILYA.J.
- 出版者
- 日本放射線影響学会
- 雑誌
- Journal of radiation research (ISSN:04493060)
- 巻号頁・発行日
- vol.40, no.4, pp.337-344, 1999-12
- 被引用文献数
- 13 33 44
Accumulated external radiation doses of residents near the Semipalatinsk nuclear test site of the former USSR are presented as a results of study by the thermoluminescence technique for bricks sampled at several settlements in 1995 and 1996. The external doses that we evaluated from exposed bricks were up to about 100 cGy for resident. The external doses at several points in the center of Semipalatinsk City ranged from a background level to 60 cGy, which was remarkably high compared with the previously reported values based on military data. INTRODUCTION A total of 459 nuclear tests were conducted by the former Union of Soviet Socialist Republics (USSR) between 1949 and 1989 at the Semipalatinsk nuclear test site (SNTS) of Kazakhstan, including 87 atmospheric, 26 on the ground, and 346 underground explosions1). The total release of the energy equivalent of trinitrotoluene (TNT) of about 18 Mt was eleven hundred times that of the Hiroshima atomic bomb. However, previous reports concerning the effects of radiation on residents near the SNTS based on data provided by the Defense Department of the former USSR2, 3) did not involve direct experimental data concerning the effective equivalent dose. They just measured some doses for particular settlements after some nuclear explosions. These did not indicate an integrated dose of the residents of all the explosions. The technique of thermoluminescence dosimetry (TLD), which had been successfully applied in dosimetry for the Hiroshima and Nagasaki atomic bombs4, 5), enabled us to evaluate the accumulated external gamma ray doses of all the nuclear explosions at specific places in the Semipalatinsk test site. The TLD technique is well-established not only for instantaneous exposure as in A-bombs (Hiroshima and Nagasaki)6) but also in prolonged exposure to natural radiation, which is used in dating7). Moreover, this technique was applicable for dosimetry studies of radioactive fallout as shown in studies of the Chernobyl accident8,9).