Triggering Collapse of the Presolar Dense Cloud Core and Injecting Short-Lived Radioisotopes with a Shock Wave. III. Rotating Three Dimensional Cloud Cores

TL;DR

This study uses detailed 3D hydrodynamic models to explore how shock waves from supernovae can trigger collapse and inject short-lived radioisotopes into presolar cloud cores, supporting supernova origin hypotheses.

Contribution

It provides the most detailed 3D simulations of shock-triggered collapse and isotope injection, considering cloud rotation and shock properties, aligning results with observed isotope abundances.

Findings

Shock waves can trigger collapse into single or multiple protostars.

Injected material shows inhomogeneous distribution due to Rayleigh-Taylor fingers.

Dilution factors match the levels needed for observed isotopic abundances.

Abstract

A key test of the supernova triggering and injection hypothesis for the origin of the solar system's short-lived radioisotopes is to reproduce the inferred initial abundances of these isotopes. We present here the most detailed models to date of the shock wave triggering and injection process, where shock waves with varied properties strike fully three dimensional, rotating, dense cloud cores. The models are calculated with the FLASH adaptive mesh hydrodynamics code. Three different outcomes can result: triggered collapse leading to fragmentation into a multiple protostar system; triggered collapse leading to a single protostar embedded in a protostellar disk; or failure to undergo dynamic collapse. Shock wave material is injected into the collapsing clouds through Rayleigh-Taylor fingers, resulting in initially inhomogeneous distributions in the protostars and protostellar disks. Cloud rotation about an axis aligned with the shock propagation direction does not increase the injection efficiency appreciably, as the shock parameters were chosen to be optimal for injection even in the absence of rotation. For a shock wave from a core-collapse supernova, the dilution factors for supernova material are in the range of $\sim 10^{-4}$ to $\sim 3 \times 10^{-4}$, in agreement with recent laboratory estimates of the required amount of dilution for $^{60}$Fe and $^{26}$Al. We conclude that a type II supernova remains as a promising candidate for synthesizing the solar system's short-lived radioisotopes shortly before their injection into the presolar cloud core by the supernova's remnant shock wave.