Abstract and subjects
We have studied the sensitivity to variations in the triple alpha and C-12(alpha,gamma) O-16 reaction rates of the production of Al-26, Ti-44, and Fe-60 in core-collapse supernovae (SNe). We used the KEPLER code to model the evolution of 15 M-circle dot, 20 M-circle dot, and 25 M-circle dot stars to the onset of core collapse and simulated the ensuing SN explosion using a piston model for the explosion and an explosion energy of 1.2 x 10(51) erg. Calculations were performed for the Anders & Grevesse and Lodders abundances. Over a range of twice the experimental uncertainty, sigma, for each helium-burning rate, the production of Al-26, Fe-60, and their ratio vary by factors of 5 or more. For some species, similar variations were observed for much smaller rate changes, 0.5 sigma or less. The production of Ti-44 was less sensitive to changes in the helium-burning rates. Production of all three isotopes depended on the solar abundance set used for the initial stellar composition.