Experimentally constrained (p,γ)89Y and (n,γ)89Y reaction rates relevant to p-process nucleosynthesis

The nuclear level density and the gamma-ray strength function have been extracted for Y-89 by using the Oslo method on Y-89(p,p gamma')Y-89 coincidence data. The gamma-ray strength function displays a low-energy enhancement consistent with previous observations in this mass region (Mo93-98). Shell-model calculations support the conclusion that the observed enhancement is due to strong, low-energy M1 transitions at high excitation energies. The data were further used as input for calculations of the Sr-88(p,gamma)Y-89 and Y-88(n,gamma)Y-89 cross sections with the TALYS reaction code. Comparison with cross-section data, where available, as well as with values from the BRUSLIB library, shows a satisfying agreement.