The Energy Spectrum of the Delayed Neutrons fromO17

Following the $\beta$-decay of ${\mathrm{N}}^{17}$ an excited state of ${\mathrm{O}}^{17}$ is formed that is unstable against neutron emission. The energy distribution of these neutrons has been measured with a hydrogen-filled cloud chamber. The results indicate that the $\beta$-decay of ${\mathrm{N}}^{17}$ leaves the ${\mathrm{O}}^{17}$ nucleus in one or more excited states and that, if there is only one excited state, it is at least 0.6 Mev wide.