r-process nucleosynthesis: a dynamical model.

The synthesis of heavy and neutron-rich elements (with atomic weight of at least 70) is reconsidered in the framework of a dynamical supernova model. The synthesis equations for the rapid neutron-capture (or the r-) process and the hydrodynamical equations for the supernova explosion are solved simultaneously. Improved systematics of nuclear parameters (nuclear masses, beta-decay half-lives) are used, and the energy release due to beta-decays as well as the energy loss due to neutrinos (and their feedback on the hydrodynamics) is taken into account. It is shown that the observed solar-system abundance curve can be reproduced fairly well by assuming only one supernova event on a time-scale of the order of 1 s. However, there are still some discrepancies which might have their origin in the approximate treatment of freezing or, more likely, in the nuclear-mass formula used.