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arXiv · 2605.08534

Unmasking Stellar Feedback-Driven Bubbles: Identification and Properties Analysis

Aaron Angress·Michael M. Foley·Sarah M. R. Jeffreson·Alyssa Goodman·Lars Hernquist
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Abstract

The identification and tracking of stellar feedback-driven galaxy bubbles is an important topic in star formation and galactic structure research. However, current observational analysis of bubbles is limited in scope; information on bubble lifetime is inaccessible. Simulation data thus provides a unique opportunity to glean some of these characteristics at high resolution. We present an investigation into the characteristics and evolution of hot, ionized bubbles in the interstellar medium of a dwarf spiral (NGC300-like) galaxy. We calculate the average radius, lifetime, temperature, density, and spatial distribution of the simulated feedback-driven bubbles using Lagrangian gas parcels, and we examine the relationship between these characteristics and the local galactic environment. We find exponential distributions of bubble lifetime and size, and we find a positive correlation between bubble lifetime and galactocentric radius. Finally, we predict how the data would appear in H$\alpha$ tracers and compare the simulated values to observations. We find an additional positive correlation between the size of the bubbles and the galactocentric radius using their H$\alpha$ tracers.

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Aaron Angress, Michael M. Foley, Sarah M. R. Jeffreson, Alyssa Goodman, Lars Hernquist. 2026-05-08. Unmasking Stellar Feedback-Driven Bubbles: Identification and Properties Analysis. https://arxiv.org/abs/2605.08534

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