Nucleosynthesis of molybdenum in neutrino-driven winds

TL;DR

This study explores how neutrino-driven winds from supernovae could produce molybdenum isotopes, addressing discrepancies between observed isotopic ratios in the solar system and SiC X grains and previous models.

Contribution

It systematically investigates nucleosynthesis in neutrino-driven winds under neutron- and proton-rich conditions, focusing on molybdenum isotope production and their potential to match observed ratios.

Findings

Neutrino-driven winds can reproduce solar system molybdenum isotope ratios.

Proton-rich conditions better explain SiC X grain isotopic ratios.

Wind parameters significantly influence molybdenum nucleosynthesis.

Abstract

Neutrino-driven winds that follow core-collapse supernovae are an exciting astrophysical site for the production of heavy elements. Although hydrodynamical simulations show that the conditions in the wind are not extreme enough for a r-process up to uranium, neutrino-driven winds may be the astrophysical site where lighter heavy elements between Sr an Ag are produced, either by the weak r-process or by the $\nu \!p$-process. However, it is still not clear if the conditions in the wind are slightly neutron-rich or proton-rich. Therefore, we investigate the nucleosynthesis in the wind for neutron- and proton-rich conditions and systematically explore the impact of wind parameters on abundances. Here we focus on molybdenum that has raised attention because several astrophysical scenarios failed to reproduce the solar system (SoS) abundance ratio of $^{92}\mathrm{Mo}$ and $^{94}\mathrm{Mo}$. Moreover, available data of SiC X grains exhibit different isotopic ratios of $^{95}\mathrm{Mo}$ and $^{97}\mathrm{Mo}$ than in the SoS. We have investigated if neutrino-driven winds can reproduce the SoS $Y(^{92}\mathrm{Mo})/Y(^{94}\mathrm{Mo})$ and can explain the origin of the $Y(^{95}\mathrm{Mo})/Y(^{97}\mathrm{Mo})$ found in SiC X.