Radiations from Indium (114) and Barium (140)

Abstract

Indium (114) emits soft conversion electrons (range \ensuremath{\sim}20mg/${\mathrm{cm}}^{2}$) and hard nuclear beta-rays of energy 1.89 Mev. Lead absorption gives quantum energies of 0.15 Mev and 0.70 Mev whereas coincidence absorption yields a maximum quantum energy of 0.90 Mev. The harder quanta are associated with an inner beta-ray group constituting less than 1.5 percent of the total beta-radiation, if with any group at all. A gamma-gamma-coincidence rate of (0.25\ifmmode\pm\else\textpm\fi{}0.02)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}3}$ coincidence per gamma-ray was noted.Barium (140) emits nuclear beta-rays having a maximum energy of 0.91 Mev and two gamma-rays having quantum energies of 0.14 Mev and 0.6 Mev as indicated by absorption in lead. Beta-gamma-coincidence data, obtained from ${\mathrm{Ba}}^{140}$ in equilibrium with ${\mathrm{La}}^{140}$ and from ${\mathrm{Ba}}^{140}$ freshly separated from its daughter element, show that the beta-ray spectrum is complex and that about twenty percent of the disintegrations proceed by way of the inner beta-ray group which is coincident in time with gamma-radiation.See note added in proof.