Radiological Physics Division Semiannual Report January June 1961 PDF Download

Data are presented from studies on the total Ra>s2/sup” /ntent, radon retention, and activity of hotspots in human bones approximately 30 yr post- adiministration of Ra. Preliminary results are reported from a study of the incidence of bone tumors following injection of Pu>s2/sup”, /a>s2/sup”/ / sup, /r>s9/sup>, /r Ca>s4/sup> / mice. Calculations were made of the radiation dose from hotspots formed in bone by these radioisotopes. The gamma spectra of 20 subjects who contained known quantities of K>s4/sup> /re obtained with several different sized NaI(Tl) crystals located at various points around the body. These spectra were analyzed to determine the variations in counting rates that resulted with each patient-crystal arrangement. The total-body gamma spectra of 12 unexposed employees were measured with the human spectrometer over a span of 30 mo. Data are tabulated on Co>s1/sup”//s4/sup> /tios. The respo nse of a scintillation counter to gamma radiation asAa function of incidence angle was measured. Studies were made on the refractive index of selected optical media. Improvements were made in the design and in the scintillator solvent for a twin scintillation fast neutron detector. Measurements were made of the skeletal and soft tissue content of Ra in normal humans whose primary source of Ra was food. Calculations of the half lives and distributions of stuble Pb and Pb>s2/sup” / the human body are discussed. Meteorological studies reported include a comparison of observed plume rise of stack effluent with values obtuined from well-known formulas, towing tank studies of horizontal turbulent air flow, and soil temperature studies. (C.H.).