Nucleosynthesis of elements between Sr and Ag in neutron- and proton-rich neutrino-driven winds

Neutrino-driven winds that follow core collapse supernovae were thought to be the site where half of the heavy elements are produced by the r-process. Although recent hydrodynamic simulations show that the conditions in the wind are not enough for the r-process, lighter heavy elements like Sr, Y, and Zr can be produced. However, it is still not clear whether the conditions in the wind are slightly neutron-rich or proton-rich. Here, we investigate the nucleosynthesis in neutrino-driven winds for both these conditions and systematically explore the impact of wind parameters on abundances. Our results show the difficulty of obtaining a robust abundance pattern in neutron-rich winds, where an over production of Sr, Y, and Zr is also likely. In proton-rich conditions, the abundances smoothly change when varying wind parameters. Constraints for wind parameters and neutrino energies and luminosities will soon become available by combining nucleosynthesis studies, like the one presented here, with new and future experimental data and observations. (paper)