Kennington, A. R.; Lotay, G.; Doherty, D. T.; Seweryniak, D.; Andreoiu, C.; Auranen, K.; Carpenter, M. P.; Catford, W.; Deibel, C. M.; Hadynska-Klek, K.; Huang, T.; Kondev, F. G.; Lauritsen, T.; Li, J.; Savard, G.; Stolze, S.; Wilson, G.; Zhu, S.
The Mg-24+ C-12 fusion reaction was used to perform a detailed gamma-ray spectroscopy study of the astrophysically important nucleus Ar-34. In particular, an experimental setup, coupling the advanced gamma-ray tracking array GRETINA with the well-established Argonne fragment mass analyzer (FMA), was employed to obtain excitation energies and spin-parity assignments for excited states in Ar-34, both above and below the proton separation energy. For the first time, an angular distribution analysis of in-beam gamma rays from fusion-evaporation reactions, using a tracking array, has been performed and Coulomb energy differences of analog states in the T = 1, A = 34 mirror system, explored from 0 to 6 MeV. Furthermore, we present a comprehensive discussion of the astrophysical Cl-33( p, gamma) stellar reaction rate, together with implications for the identification of nova presolar grains from sulfur isotopic abundances.