Particle decay branching ratios for states of astrophysical importance in 19Ne

Abstract

We have measured proton and alpha-particle branching ratios of excited states in 19Ne formed using the 19F(3He,t) reaction at a beam energy of 25 MeV. These ratios have a large impact on the astrophysical reaction rates of 15O(alpha,gamma), 18F(p,gamma) and 18F(p,alpha), which are of interest in understanding energy generation in x-ray bursts and in interpreting anticipated gamma-ray observations of novae. We detect decay protons and alpha-particles using a silicon detector array in coincidence with tritons measured in the focal plane detector of our Enge split-pole spectrograph. The silicon array consists of five strip detectors of the type used in the Louvain-Edinburgh Detector Array, subtending angles from 130 degrees to 165 degrees with approximately 14% lab efficiency. The correlation angular distributions give additional confidence in some prior spin-parity assignments that were based on gamma branchings. We measure Gamma_p/Gamma=0.387+-0.016 for the 665 keV proton resonance, which agrees well with the direct measurement of Bardayan et al.

arXiv comment5 pages, 2 figures, 3 tables. Prepared using RevTex 4 and BibTex. Further minor revisions, incl. fig. 1 font size increase, 1 table removal, and minor changes to the text

References in corpus (4)

• The Effects of Thermonuclear Reaction Rate Variations on Nova Nucleosynthesis: A Sensitivity Study
• Gamma-ray emission from novae related to positron annihilation: constraints on its observability posed by new experimental nuclear data
• The ${}^{15}$N($\mathbf{\alpha }$,$\mathbf{\gamma }$)${}^{19}$F reaction and nucleosynthesis of ${}^{19}$F
• Alpha-decay branching ratios of near-threshold states in 19Ne and the astrophysical rate of 15O(alpha,gamma)19Ne

Cited by in corpus (11)

• Charged-Particle Thermonuclear Reaction Rates: II. Tables and Graphs of Reaction Rates and Probability Density Functions
• The ${}^{15}$O($\alpha$,$\gamma$)${}^{19}$Ne Breakout Reaction and Impact on X-Ray Bursts
• Is γ-ray emission from novae affected by interference effects in the 18F(p,α)15O reaction?
• The Influence of Uncertainties in the 15O(alpha,gamma)19Ne Reaction Rate on Models of Type I X-Ray Bursts
• Lifetimes of states in 19Ne above the 15 O + alpha breakup threshold
• Lifetime of 19Ne*(4.03 MeV)
• CAKE: The Coincidence Array for K600 Experiments
• Indirect study of 19Ne states near the 18F+p threshold
• Sub-threshold states in ${}^{19}$Ne relevant to ${}^{18}$F(p,$\alpha$)${}^{15}$O
• Spin-parities of sub-threshold resonances in the ${}^{18}$F(p, $\alpha$)${}^{15}$O reaction
• The 2025 Evaluation of Experimental Thermonuclear Reaction Rates (ETR25)