@article{oai:nagasaki-u.repo.nii.ac.jp:00019494,
 author = {Shizuma, Kiyoshi and Endo, Satoru and Hoshi, Masaharu and Takada, Jun and Iwatani, Kazuo and Hasai, Hiromi and Oka, Takamitsu and Shimazaki, Tatsuya and Okumura, Yutaka and Fujita, Shoichiro and Watanabe, Tadaaki and Imanaka, Tetsuji},
 issue = {4},
 journal = {Journal of radiation research},
 month = {Dec},
 note = {Residual ^<60>Co activity in five steel samples induced by neutrons from the Nagasaki atomic bomb has been measured within about 1000 m from the hypocenter. The chemical separation of cobalt and nickel from steel samples was performed, and cobalt-enriched samples were prepared for all samples. Gamma-ray measurements were carried out with a low-background well-type germanium detector. The gamma-ray spectra for five samples were compared with the spectrum of a control sample to ensure that the observed ^<60>Co was actually induced by A-bomb neutrons. The activation of cobalt by environmental neutrons was also investigated. It has been shown that the present ^<60>Co data are consistent with earlier Hashizume's data., Journal of radiation research. 2002, 43(4), p.387-396},
 pages = {387--396},
 title = {Measurement of Residual ^<60>Co Activity Induced by Atomic-bomb Neutrons in Nagasaki and Background Contribution by Environmental Neutrons},
 volume = {43},
 year = {2002}
}