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Although the reaction 11B (p, 3 α) has been widely studied for its relevance in material science, nuclear structure, nuclear astrophysics, and fusion science, significant discrepancies exist in the data. For the channel proceeding via the ground state of 8Be , the available cross-section data shows large discrepancies of both normalization and energy scale. The present paper reports on a measurement of the 11B (p, α) cross-section using an array of large area segmented silicon detectors and low beam current on an enriched thin target with the aim of resolving the discrepancies amongst previous measurements.

A current challenge for ab initio calculations is systems that contain large continuum contributions such as Be8. We report on new measurements of radiative decay widths in this nucleus that test recent Green's function Monte Carlo calculations.Traditionally, γ ray detectors have been utilized to measure the high energy photons from the Li7(p,γ)αα reaction. However, due to the complicated response function of these detectors it has not yet been possible to extract the full γ ray spectrum from this reaction. Here we present an alternative measurement using large area Silicon detectors to detect the two α particles, which provides a practically background free spectrum and retains good energy resolution.The resulting spectrum is analyzed using a many-level multi channel R-matrix parametrization. Improved values for the radiative widths are extracted from the R-matrix fit. We find evidence for significant non-resonant continuum contributions and tentative evidence for a broad 0+ resonance at 12MeV.

Medium energy hadronic scattering and reactions at very small scattering angles, including zero degrees, can be studied with low background and high energy resolution with the K600 magnetic spectrometer at iThemba LABS. Such measurements are notoriously difficult to perform, but highly sought after due to the advantage of being very selective to excitations with low angular momentum transfer. This simplifies the analysis of the many possible contributions to the spectra due to the complex nature of the nuclear interaction. The recent addition of coincident particle and gamma detection to the zero degree capability enhances the selectivity of such a facility, which opens up a host of new opportunities to be explored. The details of the new facility and capabilities thereof are described.