Energy conservation in the thin layer approximation: VI. Bubbles and super-bubbles

TL;DR

This paper models energy conservation in the thin layer approximation for interstellar mediums, analyzing bubbles and super-bubbles like Fermi bubbles and local bubbles, with applications to observed intensities.

Contribution

It introduces analytical formulas for observed intensities of interstellar bubbles using the thin layer approximation and the theory of images.

Findings

Derived analytical formulas for observed intensity in optically thin media.

Analyzed asymmetries in shell expansion due to self-gravity and Gaussian density profiles.

Applied models to astrophysical bubbles like Fermi and local bubbles.

Abstract

We model the conservation of energy in the framework of the thin layer approximation for two types of interstellar medium (ISM). In particular, we analyse an ISM in the presence of self-gravity and a Gaussian ISM which produces an asymmetry in the advancing shell. The astrophysical targets to be simulated are the Fermi bubbles, the local bubble, and the W4 super-bubble. The theory of images is applied to a piriform curve, which allows deriving some analytical formulae for the observed intensity in the case of an optically thin medium.