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As one of a series of physics cases to demonstrate the unique benefit of the new Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas-jet target for enabling next-generation transfer reaction studies, the 14N (p,r)12N reaction was studied for the first time, using a pure jet of nitrogen, in an attempt to resolve conflicting information on the structure of 12N. A potentially new level at 4.561-MeV excitation energy in 12N was found. [ABSTRACT FROM AUTHOR]

There are a number of astrophysical environments in which the path of nucleosynthesis proceeds through proton-rich nuclei. These nuclei have traditionally not been available as beams, and thus proton-capture reactions on these nuclei could only be studied indirectly. At the Holifield Radioactive Ion Beam Facility (HRIBF), some of the first direct measurements of ( p, $ \gamma$) cross-sections on radioactive beams have been made. The Daresbury Recoil Separator (DRS) has been used to separate the recoils of interest from the unreacted primary beam and identify them in an isobutane-filled ionization counter. First data from 17F ( p, $ \gamma$18Ne and 7Be ( p, $ \gamma$8B measurements are presented. [ABSTRACT FROM AUTHOR]

While recent measurements have substantially improved our understanding of the 18F(p, α)15O reaction that is important in novae, the production of 18F is still uncertain by more than 2 orders of magnitude, due in large part to the contribution of a resonance located at Ecm = 330 keV. We developed a new technique to study resonant (p, α) reactions and employed it to measure properties of the Ecm = 183 keV resonance in 17O(p, α)14N which had been previously reported to decrease 18F production in ONeMg novae by as much as a factor of 10. The previous results were confirmed using the new technique and we now propose to use this technique to study the 18F(p, α)15O reaction. [ABSTRACT FROM AUTHOR]

Data have been obtained on exclusive single neutron knockout cross sections from 12Be to study its ground state structure. Preliminary cross sections for the first (0.32 MeV, $\ensuremath{^1\!/_2 ^-}$) and second (1.78 MeV, $\ensuremath{^5\!/_2 ^+}$, unbound) excited states in 11Be have been obtained, giving evidence of significant admixtures of both $\ensuremath{\nu(1p_{^1\!/_2})^2}$ and $\ensuremath{\nu(1d_{^5\!/_2})^2}$ configurations in the ground state of 12Be. [ABSTRACT FROM AUTHOR]

Classical novae are expected to contribute to the 1809-keV Galactic γ-ray emission by producing its precursor 26Al, but the yield depends on the thermonuclear rate of the unmeasured 25Al(p, γ)26Si reaction. Using the β decay of 26P to populate the key Jπ = 3+ resonance in this reaction, we report the first evidence for the observation of its exit channel via a 1741.6 ± 0.6(stat) ± 0.3(syst) keV primary γ ray, where the uncertainties are statistical and systematic, respectively. By combining the measured γ-ray energy and intensity with other experimental data on 26Si, we find the center-of-mass energy and strength of the resonance to be Er = 414.9 ± 0.6(stat) ± 0.3(syst) ± 0.6(lit) keV and ωγ = 23 ± 6(stat)+11-10(lit.) meV, respectively, where the last uncertainties are from adopted literature data. We use hydrodynamic nova simulations to model 26Al production showing that these measurements effectively eliminate the dominant experimental nuclear-physics uncertainty and we estimate that novae may contribute up to 30% of the Galactic 26Al. [ABSTRACT FROM AUTHOR]

A recent discussion of theoretical work on the 25Al(p, γ)26Si astrophysical reaction rate [W.A. Richter, B. Alex Brown, A. Signoracci and M. Wiescher, Phys. Rev. C 83, 065803 (2011)] omits some current and relevant experimental information in forming its scientific conclusions. Accounting for this new information has the potential to significantly alter the reaction rate derived in the paper. [ABSTRACT FROM AUTHOR]