γ−γAngular Correlation Measurements of Thermal-Neutron CaptureγRays in Magnesium, Silicon, Phosphorus, and Sulfur

A description is given of an angular correlation apparatus, using two NaI (Tl) scintillation spectrometers, which has been used to study cascades of $\gamma$ radiation following thermal neutron capture. The elements studied were magnesium, silicon, phosphorus, and sulfur. The following new spin assignments were made: the 4.93-Mev level of ${\mathrm{Si}}^{29}$, $\frac{3}{2}$; 6.38-Mev level of ${\mathrm{Si}}^{29}$, ½; 1.15-Mev level of ${\mathrm{P}}^{32}$, 1; and 3.26-Mev level of ${\mathrm{P}}^{32}$, 2. In addition, the spins of the 3.41-Mev level of ${\mathrm{Mg}}^{25}$ and the 3.22-Mev level of ${\mathrm{S}}^{33}$ have been confirmed to be $\frac{3}{2}$. Other aspects of the decay schemes are discussed.