The Internal Conversion Electrons of Several Short-Lived Neutron Induced Radioactivities

Abstract

Accurate values of the transition energy were measured for seven neutron-induced radioactivities using a permanent magnet beta-ray spectrograph. A special vacuum gate permitted the introduction of shortlived samples within twelve seconds after the end of bombardment without disturbing the vacuum in the spectrograph. Transition energies, accurate to about one percent, were determined as follows: cesium (3 hr.) 128.0 kev, cobalt (10.7 min.) 58.9 kev, columbium (6.6 min.) 41.5 kev, dysprosium (1.3 min.) 109.0 kev, dysprosium (2.6 hr.) 87.8 kev, iridium (1.5 min.) 57.4 kev, thulium (120 day) 84.8 kev. For the" five isomeric transitions, approximate values of the relative intensities of the electron lines were determined, and an assignment was made of the multipole order of the radiation, assuming electric multipole radiation.

Mixed Configurations in Nuclei

“…Both transitions D-^A (unobserved) and C-*B are thus slowed down. 15 from the lower mass number side (holes); the assumption of "purified" states in these cases, therefore, seems to be quite plausible.…”

The Radioactive Decay of Calcium 47

“…5,6 The energy of the transition is 41.5 kev as determined from the energies of the K, L, and M conversion electrons. 7 In addition, about 0.1 percent of the activity has been found to decay by emitting a 1.3-Mev 0 8 and a 0.9-Mev y. 9 Goldhaber and Muehlhause 6 set a lower limit of ^>100 years for the half-life of the ground state.…”