Speaker
Description
One aim of the upcoming Compton Spectrometer and Imager (COSI), to launch in 2027, is to measure the luminosity of gamma-rays from classical novae, presenting an exciting opportunity to constrain 18F abundance in these astrophysical phenomena. Models of classical novae have determined that nucleosynthesis and detectability of the explosion depend heavily upon the abundance of this isotope; however, precise abundance calculations remain hindered largely due to uncertainties in the rate of its main destruction pathway: the 18F(p,alpha)15O reaction. The largest uncertainties in this reaction rate are the unclear identities and properties of sub- and near-proton-threshold s-wave states in the compound nucleus, 19Ne. In order to more precisely determine the properties of 19Ne excited states, we conducted a 19F(3He,t)19Ne transfer-reaction study using the Super-Enge Split-Pole Spectrograph (SE-SPS) at the Fox Accelerator Laboratory at Florida State University. Proton and alpha decays were collected by the Silicon Array for Branching Ratio Experiments (SABRE) in coincidence with the triton reaction products detected at the focal plane. Proton asymptotic normalization coefficients were derived from ab initio symmetry-adapted no-core shell model proton-18F wavefunctions for relevant s-wave resonances. The properties of several s-wave states in 19Ne will be presented, along with their effects on the 18F(p,alpha)15O reaction rate.
| Career stage | Early-career researcher (within 5 years of PhD) |
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