The Co-Evolution of Stellar Wind-blown Bubbles and Photoionized Gas II: 3D RMHD Simulations and Tests of Semi-Analytic Models

TL;DR

This paper uses 3D RMHD simulations to test and refine a co-evolution model of feedback bubbles driven by massive stars, revealing key agreements and discrepancies that improve understanding of stellar feedback in star-forming regions.

Contribution

The study provides a detailed comparison of a semi-analytic co-evolution model with 3D RMHD simulations, highlighting its accuracy and limitations in modeling stellar feedback mechanisms.

Findings

CEM agrees within 25% for key parameters

Discrepancies due to turbulence and time-variable wind momentum

Photoionized gas reduces WBB surface area and enhances its impact

Abstract

In a companion paper (Paper I) we presented a Co-Evolution Model (CEM) in which to consider the evolution of feedback bubbles driven by massive stars through both stellar winds and ionizing radiation, outlining when either of these effects is dominant and providing a model for how they evolve together. Here we present results from three-dimensional radiation magneto-hydrodynamical (RMHD) simulations of this scenario for parameters typical of massive star-forming clouds in the Milky Way: precisely the regime where we expect both feedback mechanisms to matter. While we find that the CEM agrees with the simulations to within 25% for key parameters and modestly outperforms previous idealized models, disagreements remain. We show that these deviations originate mainly from the CEM's lack of (i) background inhomogeneity caused by turbulence and (ii) time-variable momentum enhancements in the wind-blown bubble (WBB). Additionally, we find that photoionized gas acts similarly to magnetic fields ([as in Lancaster et al. 2024a) by decreasing the WBB's surface area. This causes a decrease in the amount of cooling at the WBB's interface, resulting in an enhanced WBB dynamical impact.