Spectroscopic factors for proton unbound levels in 26Al and their influence on stellar reaction rates

The reaction 25Mg(3He, d)26Al at a bombarding energy of 15 MeV was used to populate proton unbound states in 26Al. Angular distributions were measured and spectroscopic factors extracted for nine levels from 6343 to 6680 keV excitation in 26Al. This excitation energy range corresponds to resonance energies for the 25Mg(p, γ)26Al reaction from 37 to 374 keV in the center-of-mass. Direct measurements of the resonance strengths, ωγ, had been reported for states in 26Al with Ex≥6496 keV. To obtain resonance strengths for states between 6343 and 6469 keV we combined the spectroscopic factors from the present experiment with values of ωγ and Γγ/Γ for the directly-measured resonances. We used these resonance strengths to calculate the stellar reaction rate for 25Mg(p, γ)26Al. These results show that the p-wave resonance at 92 keV(Ex=6399 keV) dominates the reaction rate in the temperature range 0.06<T9<0.13. (orig.)