Reexamination of reaction rates for a key stellar reaction of $^{14}$O($\alpha$,p)$^{17}$F

TL;DR

This paper reexamines the reaction rates of $^{14}$O($ extit{ extbf{α}}$,p)$^{17}$F, overturning previous assumptions about key nuclear states and providing updated rates with significant implications for astrophysical models.

Contribution

The study uses a detailed R-matrix analysis to correctly assign nuclear states, significantly revising the reaction rates used in astrophysical simulations.

Findings

The 6.15-MeV state is not 1$^-$ as previously thought.

The 6.286-MeV state is identified as the 1$^-$ state dominating the reaction.

Revised reaction rates differ substantially from previous estimates, especially at certain temperatures.

Abstract

The reaction rates of the key stellar reaction of $^{14}$O($\alpha$,p)$^{17}$F have been reexamined. The previous conclusion, the 6.15-MeV state ($J^{\pi}$=1$^-$) dominating this reaction rate, has been overthrown by a careful reanalysis of the previous experimental data [J. G\'{o}mez del Campo {\it et al.}, Phys. Rev. Lett. {\bf 86}, 43 (2001)]. According to the present $R$-matrix analysis, the previous 1$^-$ assignment for the 6.15-MeV state is definitely wrong. Most probably, the 6.286-MeV state is the 1$^-$ state and the 6.15-MeV state is a 3$^-$ one, and hence the resonance at $E_x$=6.286 MeV ($J^{\pi}$=1$^-$) dominates the reaction rates in the temperature region of astrophysical interests. The newly calculated reaction rates for the $^{14}$O($\alpha$,p)$^{17}$F reaction are quite different from the previous ones, for instance, it's only about 1/6 of the previous value around 0.4 GK, while it's about 2.4 times larger than the previous value around 2 GK. The astrophysical implications have been discussed based on the present conclusions.