Destruction of the cosmic γ-ray emitter 26Al in massive stars: Study of the key 26Al(n, α) reaction

Neutron destruction reactions of the cosmic gamma-ray emitter Al-26 are of importance to determine the amount of Al-26 ejected into our galaxy by supernova explosions and for Al-26 production in asymptotic giant branch stars. We performed a new measurement of the Al-26(n, alpha) reaction up to 160-keV neutron energy at the neutron time-of-flight facilities n_TOF at CERN and GELINA at EC-JRC. We provide strengths for ten resonances, six of them for the first time. We use our data to calculate astrophysical reactivities for stellar temperatures up to 0.7 GK. Our results resolve a discrepancy between the two previous direct measurements of this reaction, and indicate higher stellar destruction rates than the most recently recommended reactivity.

Automated summary

This study conducted a new measurement of the neutron destruction reactions of Al-26, providing strengths for ten resonances and calculating astrophysical reactivities for stellar temperatures up to 0.7 GK. The results resolved discrepancies between previous direct measurements and indicate higher stellar destruction rates than previously recommended.