Nuclear Levels Associated with Zirconium 95 and Niobium 95

Using sources of zirconium 95, both as a fission product and as derived from neutron capture in enriched ${\mathrm{Zr}}^{94}$, in magnetic spectrometers, a study has been made of the beta- and gamma-energies and of the half-lives associated with the radioactive decay. Zirconium 95 emits three beta-rays of energy about 910, 405, and 360 kev, each followed by a gamma-transition leading to a radioactive daughter product, niobium 95. The gamma-energies are 758, 725, and 235.2 kev. The niobium 95 decays by beta-emission, of energy 165 kev, to molybdenum 95 with accompanying gamma-energies of 753 and 768 kev. The observed transitions are found to fit a level scheme that is not incompatible with shell theory.