The existence of Al26 (t1/2=7.17×105 yr) in the interstellar medium provides a direct confirmation of ongoing nucleosynthesis in the Galaxy. The presence of a low-lying 0+ isomer (Al26m), however, severely complicates the astrophysical calculations. We present for the first time a study of the Al26m(d,p)Al27 reaction using an isomeric Al26 beam. The selectivity of this reaction allowed the study of â.,"=0 transfers to T=1/2, and T=3/2 states in Al27. Mirror symmetry arguments were then used to constrain the Al26m(p,γ)Si27 reaction rate and provide an experimentally determined upper limit of the rate for the destruction of isomeric Al26 via radiative proton capture reactions, which is expected to dominate the destruction path of Al26m in asymptotic giant branch stars, classical novae, and core collapse supernovae.
Publication Source (Journal or Book title)
Physical Review Letters
Almaraz-Calderon, S., Rehm, K., Gerken, N., Avila, M., Kay, B., Talwar, R., Ayangeakaa, A., Bottoni, S., Chen, A., Deibel, C., Dickerson, C., Hanselman, K., Hoffman, C., Jiang, C., Kuvin, S., Nusair, O., Pardo, R., Santiago-Gonzalez, D., Sethi, J., & Ugalde, C. (2017). Study of the Alm 26 (d,p) Al 27 Reaction and the Influence of the Al 26 0+ Isomer on the Destruction of Al 26 in the Galaxy. Physical Review Letters, 119 (7) https://doi.org/10.1103/PhysRevLett.119.072701