Supernova Ejecta in Ocean Cores Used as Time Constraints for Nearby Stellar Groups

TL;DR

This study uses supernova ejecta in ocean cores to constrain the origins of nearby stellar groups, identifying Tucana-Horologium and Upper Centaurus-Lupus as likely supernova birth-sites based on timing and stellar data.

Contribution

It introduces a method to link supernova ejecta timelines with stellar group ages to identify likely supernova progenitor sites.

Findings

Tucana-Horologium likely hosted the supernova 7-9 Myr ago.

Upper Centaurus-Lupus likely hosted the supernova 2-3 Myr ago.

Upper Scorpius and Lower Centaurus-Crux are unlikely supernova sites.

Abstract

Evidence of a supernova event, discussed in Wallner et al., was discovered in the deep-sea crusts with two signals dating back to 2-3 and 7-9 Myr ago. In this contribution, we place constraints on the birth-site of the supernova progenitors from the ejecta timeline, the initial mass function, and the ages of nearby stellar groups. We investigated the Scorpius-Centaurus OB Association, the nearest site of recent massive star formation, and the moving group Tucana-Horologium. Using the known stellar mass of the remaining massive stars within these subgroups and factoring in travel time for the ejecta, we have constrained the ages and masses of the supernova progenitors by using the initial mass function and then compared the results to the canonical ages of each subgroup. Our results identify the Upper Scorpius and Lower Centaurus-Crux subgroups as unlikely birth-sites for these supernovae. We find that Tucana-Horologium is the likely birth-site of the supernova 7-9 Myr ago and Upper Centaurus-Lupus is the likely birth-site for the supernova 2-3 Myr ago.