@article{oai:repo.qst.go.jp:00044277,
 author = {Shirakawa, Yoshiyuki and 白川 芳幸},
 issue = {213},
 journal = {Nuclear Instruments & Methods in Physics Research Section B},
 month = {Jan},
 note = {This paper describes directional gamma ray detectors with different types of scintillators. The detectors, which positively increase directional sensitivity to incident gamma rays, have been developed to measure directions, energies and counts of gamma rays, and to search for radioactive materials such as orphan radioisotopes or contaminations. Experimental results have shown that proposed directional detectors have a potential for practical use in real fields and will contribute to radiation protection and safety.},
 pages = {255--259},
 title = {Developments of directional detectors with NaI(Tl)/BGO scintillators},
 year = {2004}
}