[The applicability of pions to cancer radiotherapy. III. Measurement of x-ray and gamma-rays by NaI detector for the determination of the peak-region in pi- meson exposure].
A method of externally observing the stop-region of pi- meson for monitoring during exposure to a patient is discussed. Negative pi mesic X-rarys, gamma-rays and neutrons are emitted from the region where pi- mesons stop and produce stars. These radiations can be detected outside the exposed patient. Water phantom as normal tissue equivalent material was exposed by pi- mesons at various depths. The resulting gamma-ray yields were determined by counting the gamma-rays in coincidence with incident pi- mesons using a sodium iodide (NaI) detector. This type of gamma-ray measuring system is useful to make sure that the peak position of the depth-dose distribution in the patient is exactly situated at the desired one during exposure. It is suggested that the scintillation camera with a multiholecollimator is a powerful and convenient tool for the two dimensional peak positioning.
D005720:Gamma Rays; D006801:Humans; D009369:Neoplasms / Q000532:radiotherapy; D009502:Neutrons; D011834:Radiation Monitoring / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage; D012588:Scintillation Counting / Q000295:instrumentation / Q000379:methods*; D014965:X-Rays