Investigation of detection threshold energy of high energy cascade shower using a thermoluminescence sheet and a hot gas reader

Abstract A thermoluminescence (TL) sheet was developed to detect a cascade shower produced by a high energy γ ray. A hot gas reader system for this TL sheet was also developed. For the investigation of detection threshold energy for the cascade shower, TL sheets were exposed to cosmic rays at Mt. Fuji together with X-ray films, and scanned by the hot gas reader. From the results of this experiment, it is concluded that the cascade shower produced by the high energy γ ray ( ≧ 10 TeV ) is detectable at the maximum development of the cascade shower.