Bibliographic Details
| Title: |
Spin-parities of sub-threshold resonances in the $^{18}$F(p, $\alpha$)$^{15}$O reaction |
| Authors: |
Portillo, F., Longland, R., Cooper, A. L., Hunt, S., Laird, A. M., Marshall, C., Setoodehnia, K. |
| Source: |
Phys. Rev. C 107, 035809 (2023) |
| Publication Year: |
2023 |
| Collection: |
Nuclear Experiment |
| Subject Terms: |
Nuclear Experiment |
| More Details: |
The $^{18}$F(p, $\alpha$)$^{15}$O reaction is key to determining the $^{18}$F abundance in classical novae. However, the cross section for this reaction has large uncertainties at low energies largely caused by interference effects. Here, we resolve a longstanding issue with unknown spin-parities of sub-threshold states in $^{19}$Ne that reduces these uncertainties. The $^{20}$Ne($^3$He, $^4$He)$^{19}$Ne neutron pick-up reaction was used to populate $^{19}$Ne excited states, focusing on the energy region of astrophysical interest ($\approx$ 6 - 7 MeV). The experiment was performed at the Triangle Universities Nuclear Laboratory using the high resolution Enge split-pole magnetic spectrograph. Spins and parities were found for states in the astrophysical energy range. In particular, the state at 6.133 MeV (E$_{r}^{\text{c.m.}} = -278$ keV) was found to have spin and parity of $3/2^+$ and we confirm the existence of an unresolved doublet close to 6.288 MeV (E$_{r}^{\text{c.m.}} = -120$ keV) with J$^{\pi}$ = $1/2^+$ and a high-spin state. Using these results, we demonstrate a significant factor of two decrease in the reaction rate uncertainties at nova temperatures.
Comment: 15 pages, 6 figures, accepted in Phys. Rev. C. Corrected typos and references |
| Document Type: |
Working Paper |
| DOI: |
10.1103/PhysRevC.107.035809 |
| Access URL: |
http://arxiv.org/abs/2303.03596 |
| Accession Number: |
edsarx.2303.03596 |
| Database: |
arXiv |
