Converted Gamma-Radiation from Silver, Cadmium, Indium, Praseodynium, and Rhenium

Abstract

By use of beta-spectrometers and absorption methods the half-lives and energy characteristics of radioactive isotopes of silver, cadmium, indium, praseodymium, and rhenium have been determined. The activities studied were induced by neutron capture in the pile.Silver of half-life 282 days had gamma-rays of energy 114.2, 655, 880 kev and 1.38 Mev. Cadmium appears to yield several radioactivities; one of which is a positron emitter and converted gamma-rays of 86.3 and 336.9 Kev are observed. The well known 48-day activity in indium has a converted gamma-ray whose energy is more closely determined as 190.9 Kev. Praseodymium also displays a complex decay curve, but associated with a short half-life previously reported as 19.2 hours are gamma-rays of 133.7, 328.9, 489.6, and 624 Kev, and by absorption a high energy gamma-ray of 2.1 Mev. Rhenium is strongly activated in the pile, yielding two radioactivities, of half-lives 16 hours and 91 hours. A converted gamma-ray of 153.6 Kev is found for the short-lived activities, and gamma-energies of 122.7, 135.8, 127.5, and 640 Kev exist for the longer-lived activity.