학술논문
New $\gamma$-ray Transitions Observed in $^{19}$Ne with Implications for the $^{15}$O($\alpha$,$\gamma$)$^{19}$Ne Reaction Rate
Document Type
Working Paper
Author
Hall, M. R.; Bardayan, D. W.; Baugher, T.; Lepailleur, A.; Pain, S. D.; Ratkiewicz, A.; Ahn, S.; Allen, J. M.; Anderson, J. T.; Ayangeakaa, A. D.; Blackmon, J. C.; Burcher, S.; Carpenter, M. P.; Cha, S. M.; Chae, K. Y.; Chipps, K. A.; Cizewski, J. A.; Febbraro, M.; Hall, O.; Hu, J.; Jiang, C. L.; Jones, K. L.; Lee, E. J.; O'Malley, P. D.; Ota, S.; Rasco, B. C.; Santiago-Gonzalez, D.; Seweryniak, D.; Sims, H.; Smith, K.; Tan, W. P.; Thompson, P.; Thornsberry, C.; Varner, R. L.; Walter, D.; Wilson, G. L.; Zhu, S.
Source
Phys. Rev. C 99, 035805, 2019
Subject
Language
Abstract
The $^{15}$O($\alpha$,$\gamma$)$^{19}$Ne reaction is responsible for breakout from the hot CNO cycle in Type I x-ray bursts. Understanding the properties of resonances between $E_x = 4$ and 5 MeV in $^{19}$Ne is crucial in the calculation of this reaction rate. The spins and parities of these states are well known, with the exception of the 4.14- and 4.20-MeV states, which have adopted spin-parities of 9/2$^-$ and 7/2$^-$, respectively. Gamma-ray transitions from these states were studied using triton-$\gamma$-$\gamma$ coincidences from the $^{19}$F($^{3}$He,$t\gamma$)$^{19}$Ne reaction measured with GODDESS (Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies) at Argonne National Laboratory. The observed transitions from the 4.14- and 4.20-MeV states provide strong evidence that the $J^\pi$ values are actually 7/2$^-$ and 9/2$^-$, respectively. These assignments are consistent with the values in the $^{19}$F mirror nucleus and in contrast to previously accepted assignments.