News from the p-process: is the s-process a troublemaker?

The most detailed calculations of the p-process call for its development in the O/Ne layers of Type II supernovae. In spite of their overall success i n reproducing the solar system content of p-nuclides, they suggest a signif icant underproduction of the light Mo and Ru isotopes. On grounds of a mode l for the explosion of a 25 M-circle dot star with solar metallicity, we de monstrate that this failure might just be related to the uncertainties left in the rate of the Ne-22(alpha ,n) Mg-25 neutron producing reaction. The l atter indeed has a direct impact on the distribution of the s-process seeds for the p-process.