ON THE METHOD OF IDENTIFICATION AND THE ACTIVITY CALCULATION OF SHORT-LIVING GAMMA EMITTERS
Some results of researching for identification and calculation the activity of radionuclides in gamma spectrometry of samples containing many short-lived low activity nuclides (half-life less than 1 hour) was presented. The need to identify such radionuclides can be linked to the study of the effect of cosmic radiation on various chemical elements compounds and to observation the experiments of possible carrying out low-energy nuclear reactions. The step-by-step guide for the process of analyzing the instrumental spectrum obtained from radiation of a lithium preparation after its exposure with cosmic rays with the view to identify by the energies of gamma radiation and by the half-lives of nuclides was given. The activity of the identified radionuclides was calculated. The results of the calculation of the activity of 5 identified, the activity of which ranged from 0,1 to 2 Bq, and whose atomic numbers ranged from 21 (46mSc) to 69 (176Tm), are presented. The effects from Compton radiation of high-energy gamma-quanta and the beta-particles braking radiation on the results of the activity calculating were noted. It was concluded that, with this reason, the so high estimate of the activity values during the gamma analysis of low activity samples was made. A method for correcting such an overestimation is considered on practical examples.