The Disintegration of Ruthenium 103 and Palladium 103

The beta- and gamma-ray spectra of ${\mathrm{Ru}}^{103}$ (43 days), ${\mathrm{Pd}}^{103}$ (17 days), and ${\mathrm{Rh}}^{103\mathrm{m}}$ (56 min.) have been investigated in a magnetic lens spectrograph. ${\mathrm{Ru}}^{103}$ disintegrates with the emission of two beta-ray groups of end-point energies 0.684 Mev (six percent) and 0.204 Mev (94 percent) together with a gamma-ray of 0.494 Mev and an internally converted gamma-ray of 40.4-kev energy. ${\mathrm{Pd}}^{103}$ disintegrates by orbital electron capture. The spectrum consists of an electron line at 36.9 kev, shown to be due to $L$ electrons from a highly converted gamma-ray of 40.4-kev energy, together with Auger electrons. The spectrum of the metastable ${\mathrm{Rh}}^{103\mathrm{m}}$, whose half-life has been determined as 56 min., consists of an $L$ conversion line for a gamma-ray of 40.4 kev, with some indication of the presence of the $K$-line. ${\mathrm{Ru}}^{97}$ (2.8 days) was also measured and found to emit a gamma-ray of 0.217 Mev.