Spins and Parities of Highly Excited States inMg24

Abstract

From a study of the reaction ${\mathrm{C}}^{12}({\mathrm{O}}^{16},{\alpha }_1){\mathrm{Mg}}^{24}\left({\alpha }_2\right){\mathrm{Ne}}^{20}$, spins and parities have been measured for states in ${\mathrm{Mg}}^{24}$ at the following excitation energies (in MeV): 12.10 ($4^{+}$), 12.45 ($7^{-}$), 13.07 ($5^{-}$), 14.41 ($4^{+}$), 16.07 ($6^{+}$), and 16.59 ($6^{+}$). Branching ratios were measured for several states in ${\mathrm{Mg}}^{24}$ with $13<~E_{\mathrm{exc}}<~23$ MeV decaying to the following states in ${\mathrm{Ne}}^{20}$: $0^{+}$ (ground state), $2^{+}$ (1.63 MeV), and $4^{+}$ (4.25 MeV). These results permit the elimination of several postulated structures for the states in question.