Radioactivity of neutron-rich oxygen, fluorine, and neon isotopes

The $\gamma$ radiation and neutrons emitted following the $\beta$ decays of ${}^{24}\mathrm{O},$ ${}^{25–27}\mathrm{F},$ and ${}^{28-30}\mathrm{Ne}$ have been measured. The nuclides were produced in the quasifragmentation of a 2.8 GeV ${}^{36}\mathrm{S}$ beam, separated in-flight and identified through time-of-flight and energy-loss measurements. The ions were stopped in a silicon detector telescope, which was used to detect the $\beta$ particles emitted in their subsequent radioactive decay. The coincident $\gamma$ rays were measured using four large volume germanium detectors mounted close to the implantation point and the neutrons were detected using 42 ${}^3\mathrm{He}$ proportional counters. The measured $\gamma$-ray energy spectra are compared with shell model calculations and, where available, the level energies deduced from multinucleon transfer reactions.