On the origin of the Ca-Ti-Cr isotopic anomalies in the inclusion EK-1-4-1 of the Allende Meteorite

TL;DR

This study investigates the nucleosynthesis origins of Ca-Ti-Cr isotopic anomalies in a meteorite inclusion, updating nuclear physics data and exploring astrophysical scenarios that could produce these anomalies.

Contribution

It introduces updated nuclear physics data and demonstrates two possible astrophysical scenarios that explain the isotopic anomalies in the meteorite inclusion.

Findings

Two astrophysical scenarios can reproduce the anomalies: low entropy (SN Ia) and high entropy (SN II neutrino wind).

Updated nuclear data improve the modeling of nucleosynthesis processes.

Both scenarios are consistent with observed isotopic anomalies.

Abstract

In the framework of our investigation to explain the nucleosynthesis origin of the correlated Ca-Ti-Cr isotopic anomalies in the Ca-Al-rich ''FUN'' inclusion EK-1-4-1 of the Allende meteorite, the nuclear-physics basis in the neutron-rich N=28 region has been updated by including recent experimental data on beta-decay properties and microscopic predictions of neutron-capture cross sections. Charged-particle and subsequent r-process calculations within an entropy-based approach were performed using a complete reaction network. It is shown that there exist two astrophysical scenarios within which the observed isotopic anomalies can be reproduced simultaneously; one at low entropies (about 10) which confirms the earlier suggestrd Sn Ia mechanism, and another at high entropies (about 150) which could be compatible with the neutrino-wind scenario of a SN II.