Radiations of 53-MinI134and 86-SecI136

The radiations from 53-min ${\mathrm{I}}^{134}$ and 86-sec ${\mathrm{I}}^{136}$ were examined with a scintillation spectrometer and compared with known radiations. The former was found to emit beta rays of 1.5±0.1 Mev and 2.5±0.2 Mev maximum energy, and $\gamma$ rays of the following energies: 0.86±0.01 Mev, 1.10±0.03 Mev, and 1.78±0.05 Mev. Coincidence measurements showed that the 2.5-Mev $\beta$ rays were followed by the 0.86-Mev $\gamma$ rays and that the first excited level in ${\mathrm{Xe}}^{134}$ is very likely at 0.86 Mev as predicted by the systematics of even-even nuclei. There is some evidence for two additional weak $\gamma$ rays at 120 kev and 200 kev.