The cross section of the ${}^{88}\mathrm{Sr}(p,\gamma {)}^{89}\mathrm{Y}$ reaction was determined by in-beam measurements at energies $E_p=1.4\mathrm{}–5\mathrm{MeV}$ relevant to the nucleosynthetic p process. At $E_p>~3.5\mathrm{MeV},$ the γ angular distributions were obtained by using one HPGe detector of 80% relative efficiency, whereas at $E_p<~3.5\mathrm{MeV}$ they were measured by means of an array of four HPGe detectors all shielded with BGO crystals for Compton background supression. Three of them had a relative efficiency ${\epsilon }_r\approx 100\%,$ whereas the remaining one had ${\epsilon }_r\approx 78\%.$ From the resulting cross sections, that lie in the 0.5-μb–5-mb range, astrophysical S factors and reaction rates have been derived. Cross sections, S factors, and reaction rates have also been calculated by means of the statistical model code MOST. A very good agreement between the experimental data and the theoretical predictions has been found.

• Received 21 May 2002

DOI:https://doi.org/10.1103/PhysRevC.67.015801