Study of low-lying resonances in ²⁶Si relevant for understanding the nucleosynthesis of Galactic ²⁶Al

The ²⁵Al (p,γ) ²⁶Si proton-capture reaction is critical in understanding the nucleosynthesis of the radioactive isotope ²⁶Al throughout the Galaxy. This reaction plays a key role re-directing the flux of nuclear material away from the ground state (²⁶Al^g), in favor of its short-lived isomeric state (²⁶Al^m), which bypasses the gamma-ray emission but is observed in, for example, isotopic abundances of ²⁶Mg in meteorites. Uncertainties in the ²⁵Al(p,γ)²⁶Si reaction are dominated by the nuclear properties of low-lying proton-unbound states in ²⁶Si.

A high-sensitivity spectroscopy study of ²⁶Si was performed at the John D. Fox laboratory at Florida State University (FSU), using a neutron/γ-ray coincidence measurement of the ²⁴Mg(3He,nγ)²⁶Si reaction. The experiment was carried out using the CATRiNA neutron detector array, which was developed for this project; in coincidence with the FSU HPGe Clover detectors. Results of this measurement and their astrophysical implications for the ²⁵Al(p,γ)²⁶Si reaction rate, will be present in this talk.