Modelling the thermal X-ray emission around the Galactic centre from colliding Wolf-Rayet winds

TL;DR

This study models the thermal X-ray emission near the Galactic centre by simulating colliding Wolf-Rayet winds, successfully matching observations and revealing the influence of SMBH outflows on hot gas distribution.

Contribution

It introduces hydrodynamic simulations of Wolf-Rayet star winds near Sgr A* to interpret X-ray data, highlighting the role of SMBH outflows in shaping the emission.

Findings

Model reproduces observed X-ray spectral shape.

Hot gas is primarily from shocked WR winds.

Moderate SMBH outflow best fits current data.

Abstract

We compute the thermal X-ray emission from hydrodynamic simulations of the 30 Wolf-Rayet (WR) stars orbiting within a parsec of Sgr A$^*$, with the aim of interpreting the Chandra X-ray observations of this region. The model well reproduces the spectral shape of the observations, indicating that the shocked WR winds are the dominant source of this thermal emission. The model X-ray flux is tied to the strength of the Sgr A$^*$ outflow, which clears out hot gas from the vicinity of Sgr A$^*$. A moderate outflow best fits the present-day observations, even though this supermassive black hole (SMBH) outflow ended $\sim$100 yr ago.