${}^{72}\mathrm{As}$ is a promising positron emitter for diagnostic imaging that can be employed locally using a ${}^{72}\mathrm{Se}$ generator. However, current reaction pathways to ${}^{72}\mathrm{Se}$ have insufficient nuclear data for efficient production using regional 100–200 MeV high-intensity proton accelerators. In order to address this deficiency, stacked-target irradiations were performed at LBNL, LANL, and BNL to measure the production of the ${}^{72}\mathrm{Se}/{}^{72}\mathrm{As}$ positron emission tomography (PET) generator system via ${}^{75}\mathrm{As}(p,x)$ between 35 and 200 MeV. This work provides the most well-characterized excitation function for ${}^{75}\mathrm{As}(p,4n){}^{72}\mathrm{Se}$ starting from threshold. Additional focus was given to report the first measurements of ${}^{75}\mathrm{As}(p,x){}^{68}\mathrm{Ge}$ and bolster an already robust production capability for the highly valuable ${}^{68}\mathrm{Ge}/{}^{68}\mathrm{Ga}$ PET generator. Thick target yield comparisons with prior established formation routes to both generators are made. In total, high-energy proton-induced cross sections are reported for 55 measured residual products from ${}^{75}\mathrm{As}, {}^{\mathrm{nat}}\mathrm{Cu}$, and ${}^{\mathrm{nat}}\mathrm{Ti}$ targets, where the latter two materials were present as monitor foils. These results were compared with literature data as well as the default theoretical calculations of the nuclear model codes talys, coh, empire, and alice. Reaction modeling at these energies is typically unsatisfactory due to few prior published data and many interacting physics models. Therefore, a detailed assessment of the talys code was performed with simultaneous parameter adjustments applied according to a standardized procedure. Particular attention was paid to the formulation of the two-component exciton model in the transition between the compound and preequilibrium regions, with a linked investigation of level density models for nuclei off of stability and their impact on modeling predictive power. This paper merges experimental work and evaluation techniques for high-energy charged-particle isotope production in an extension to an earlier study of this kind.

Background: A number of accelerator-based isotope production facilities utilize 100- to 200-MeV proton beams due to the high production rates enabled by high-intensity beam capabilities and the greater diversity of isotope production brought on by the long range of high-energy protons. However, nuclear reaction modeling at these energies can be challenging because of the interplay between different reaction modes and a lack of existing guiding cross-section data.

The gamma reaction history diagnostic at the National Ignition Facility has the capability to determine a number of important performance metrics for cryogenic deuterium-tritium implosions: the fusion burn width, bang time and yield, as well as the areal density of the compressed ablator. Extracting those values from the measured γ rays of an implosion, requires accounting for a γ-ray background in addition to the impulse response function of the instrument. To address these complications, we have constructed a model of the γ-ray signal, and are developing a simultaneous multi-shot fitting routine to constrain its parameter space.

The transient-field technique has been used to measure the g factors of yrast states in ${}_{}{}^{86}{}_{}{}^{}\mathrm{Zr}$ over the spin region I=8ħ–14ħ in order to ascertain the nature of the alignments at the first and second backbends. The states of interest were populated in the reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ${(}^{77}$Se,3n) at 260 MeV. The results demonstrate that the first crossing at the $8_1^{+}$ state involves the alignment of neutron ${\mathit{g}}_{9/2}$ quasiparticles, and that proton ${\mathit{g}}_{9/2}$ quasiparticles align at higher spin.