3D AMR simulations of G2 as an outflow

TL;DR

This study uses 3D adaptive mesh refinement simulations to model G2 as an outflow from a low-mass star, comparing results with observations to understand its evolution and properties.

Contribution

It introduces a detailed hydrodynamic model of G2 as a stellar outflow, providing new insights into its velocity, mass-loss rate, and interaction with the surrounding medium.

Findings

A massive, slow outflow reproduces G2's observed properties.

A faster outflow can explain material following G2 on the same orbit.

Simulations match observed position-velocity diagrams.

Abstract

We study the evolution of G2 in a \textit{Compact Source Scenario}, where G2 is the outflow from a low-mass central star moving on the observed orbit. This is done through 3D AMR simulations of the hydrodynamic interaction of G2 with the surrounding hot accretion flow. A comparison with observations is done by means of mock position-velocity (PV) diagrams. We found that a massive ($\dot{M}_\mathrm{w}=5\times 10^{-7} \;M_{\odot} \; \mathrm{yr^{-1}}$) and slow ($v_\mathrm{w}=50 \;\mathrm{km\; s^{-1}}$) outflow can reproduce G2's properties. A faster outflow ($v_\mathrm{w}=400 \;\mathrm{km\; s^{-1}}$) might also be able to explain the material that seems to follow G2 on the same orbit.