The nuclide ${\mathrm{Ne}}^{24}$ has been produced by bombarding a neon gas target with 1.5-Mev tritons, the reaction being ${\mathrm{Ne}}^{22}(t, p){\mathrm{Ne}}^{24}$. Beta and gamma scintillation spectrometers with coincidence circuits were used to study this nuclide. ${\mathrm{Ne}}^{24}$ decays with a half-life of 3.38±0.02 min, emitting negative beta groups of 1.98±0.05 and 1.10±0.05 Mev. This decay is also accompanied by gamma rays of 472±5 and 878±9 kev with relative intensities of 100 to 8, respectively. The excited levels in ${\mathrm{Na}}^{24}$ corresponding to the above transitions are at 0.472 and 1.35 Mev. The 0.472-Mev level is an isomeric state with a half-life of the order of 20 milliseconds. The spins and parities of the ${\mathrm{Na}}^{24}$ ground state, 0.472-Mev, and 1.35-Mev levels are 4+, 1+, and 1+, respectively. The ${\mathrm{Ne}}^{24}$-${\mathrm{Na}}^{24}$ energy difference is 2.449±0.035 Mev, and the ${\mathrm{Ne}}^{24}$ mass is 24.001195±0.000040 atomic mass units.

• Received 12 January 1956

DOI:https://doi.org/10.1103/PhysRev.102.426