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A current challenge for ab initio calculations is systems that contain large continuum contributions such as 8Be. We report on new measurements of radiative decay widths in this nucleus that test recent Greens function Monte Carlo calculations. Traditionally, {gamma} ray detectors have been utilized to measure the high energy photons from the 7Li(p, {gamma}){alpha}{alpha} reaction. However, due to the complicated response function of these detectors it has not yet been possible to extract the full {gamma} ray spectrum from this reaction. Here we present an alternative measurement using large area Silicon detectors to detect the two {alpha} 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 12 MeV.
The $^{18}{rm O}(p,alpha)^{15}{rm N}$ reaction is of primary importance in several astrophysical scenarios, including fluorine nucleosynthesis inside AGB stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus the indirect meas
Background: Type I x-ray bursts are the most frequent thermonuclear explosions in the galaxy, resulting from thermonuclear runaway on the surface of an accreting neutron star. The $^{30}$S($alpha$,p) reaction plays a critical role in burst models, ye
A study of the 7Li(9Be,4He9Be)3H reaction at E{beam}=70 MeV has been performed using resonant particle spectroscopy techniques and provides a measurement of alpha-decaying states in 13C. Excited states are observed at 12.0, 13.4, 14.1, 14.6, 15.2, 16
In the model calculations of heavy element nucleosynthesis processes the nuclear reaction rates are taken from statistical model calculations which utilize various nuclear input parameters. It is found that in the case of reactions involving alpha pa
The production of 26 Al in massive stars is sensitive to the 23 Na(a,p) 26 Mg cross section. Recent experimental data suggest the currently recommended cross sections are underestimated by a factor of 40. We present here differential cross sections f