Nuclear correlations and the r-process

TL;DR

This paper demonstrates that incorporating long-range nuclear correlations into mass models significantly influences r-process nucleosynthesis, reducing abundance troughs and aligning predictions more closely with observed solar system element distributions.

Contribution

It introduces the impact of nuclear mass correlations on r-process element synthesis, highlighting their role in improving abundance predictions.

Findings

Correlations suppress magic number effects in nuclear masses.

Including correlations smoothens separation energies, reducing abundance troughs.

Results align r-process predictions more closely with solar system abundances.

Abstract

We show that long-range correlations for nuclear masses have a significant effect on the synthesis of heavy elements by the r-process. As calculated by Delaroche et al. [1], these correlations suppress magic number effects associated with minor shells. This impacts the calculated abundances before the third r-process peak (at mass number A~195), where the abundances are low and form a trough. This trough and the position of the third abundance peak are strongly affected by the masses of nuclei in the transition region between deformed and spherical. Based on different astrophysical environments, our results demonstrate that a microscopic theory of nuclear masses including correlations naturally smoothens the separation energies, thus reducing the trough and improving the agreement with observed solar system abundances.