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A measurement of the $^{50}\mathrm{Ti}(d,p)^{51}\mathrm{Ti}$ reaction at 16 MeV was performed using the Super Enge Split-Pole Spectrograph to measure the magnitude of the $N=32$ subshell gap in Ti. Seven states were observed that had not been observed in previous $(d,p)$ measurements, and the $L$ transfer values for six previously measured states were either changed or measured for the first time. The results were used to determine single neutron energies for the ${p}_{3/2}$, ${p}_{1/2}$, and ${f}_{5/2}$ orbitals. The resulting single neutron energies in $^{51}\mathrm{Ti}$ confirm the existence of the $N=32$ gap in Ti. These single neutron energies and those from previous measurements in $^{49}\mathrm{Ca}$, $^{53}\mathrm{Cr}$, and $^{55}\mathrm{Fe}$ are compared to values from a covariant density functional theory calculation.

The Silicon Array for Branching Ratio Experiments (SABRE) has been developed for use to study reactions of interest to nuclear structure and astrophysics . The array has been incorporated into the Super Enge Split-Pole Spectrograph (SE-SPS) experimental setup at Florida State University’s John D. Fox accelerator laboratory to detect charged-particle decays in coincidence with reaction products detected by the SE-SPS focal plane detector. Its construction and electronics processing are discussed, as well as the commissioning data used to validate its performance.

The National Ignition Facility (NIF) provides the opportunity to study nuclear reactions under controlled conditions at high temperatures and pressures at a level never before achieved. However, the timescale of the deuterium-tritium (DT) implosion is only a few nanoseconds, making data collection and diagnostics very challenging. One method that has been proposed for obtaining additional information about the conditions of the implosion is to activate a dopant material using the $\ensuremath{\alpha}$ particles produced from the DT fuel as a diagnostic. The yield of the activated material can give a measure of the mixing that occurs in the capsule. One of the reactions that has been proposed is $^{10}\mathrm{B}(\ensuremath{\alpha},n)\phantom{\rule{0.16em}{0ex}}^{13}\mathrm{N}$ as it produces a radioactive reactant product with a convenient half-life of $\ensuremath{\approx}10\phantom{\rule{0.16em}{0ex}}\mathrm{min}$. Although this reaction has several advantages for the application at hand, it has not seen much study in the present literature, resulting in large uncertainties in the cross section. Furthermore, for the current application, the cross section must be well characterized. With this motivation, the $^{10}\mathrm{B}(\ensuremath{\alpha},n)\phantom{\rule{0.16em}{0ex}}^{13}\mathrm{N}$ cross section has been remeasured for $2.2l{E}_{\ensuremath{\alpha}}l4.9\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}$ with the angle-integrated ground-state cross section reported for the first time. The present results, combined with previous measurements, allow for a determination of the cross section to a significantly higher degree of accuracy and precision than obtained previously and are shown to be consistent with thick-target measurements. Preliminary calculations are performed to test the feasibility of this reaction as a diagnostic for a NIF implosion.