A Solar System formation analogue in the Ophiuchus star-forming complex

TL;DR

This paper investigates how the Solar System's short-lived radionuclides, especially $^{26}$Al, could have been enriched by nearby supernovae in the Ophiuchus star-forming region, providing insights into early Solar System formation.

Contribution

It demonstrates that $^{26}$Al in Ophiuchus likely originated from multiple supernovae, enriched the gas before core formation, and exhibits a broad enrichment distribution, informing Solar System formation models.

Findings

$^{26}$Al is enriched by supernovae in Ophiuchus.

Enrichment spans about two orders of magnitude.

Implication of a global heating event in early Solar System.

Abstract

Anomalies among the daughter nuclei of the extinct short-lived radionuclides (SLRs) in the calcium-aluminum-rich inclusions (CAIs) indicate that the Solar System must have been born near a source of the SLRs so that they could be incorporated before they decayed away. $\gamma$-rays from one such living SLR, $^{26}$Al, are detected in only a few nearby star-forming regions. Here we employ multi-wavelength observations to demonstrate that one such region, Ophiuchus, containing many pre-stellar cores that may serve as analogs for the emerging Solar System, is inundated with $^{26}$Al from the neighboring Upper-Scorpius association, and so may provide concrete guidance for how SLR enrichment proceeded in the Solar System complementary to the meteoritics. We demonstrate via Bayesian forward modeling drawing on a wide range of observational and theoretical results that this $^{26}$Al likely 1) arises from supernova explosions, 2) arises from multiple stars, 3) has enriched the gas prior to the formation of the cores, and 4) gives rise to a broad distribution of core enrichment spanning about two orders of magnitude. This means that if the spread in CAI ages is small, as it is in the Solar System, protoplanetary disks must suffer a global heating event.