isotope[74]Se/[78]Kr versus [84]Sr/[78]Kr from the model yields, with both ratios normalised to their respective solar values. The light and dark grey shaded areas represent, respectively, values a factor of two and three from the solar ratio (black filled circle). The different sets of models are represented by different types of symbols as indicated in the legend on the right-hand side. The mass of the star is indicated as a small number next to its corresponding symbol. Filled and empty symbols represent the yields including or not, respectively, the radiogenic contribution from all unstable isotopes. The only significant radiogenic contribution comes from [74]Br to [74]Se.