Inflow-Outflow Solution with Stellar Winds and Conduction near Sgr A*

TL;DR

This paper develops a comprehensive 2-temperature plasma flow model near Sgr A* that incorporates stellar winds, conduction, and relativistic effects, successfully fitting X-ray and sub-mm observations to understand accretion and outflow behaviors.

Contribution

It introduces a novel, self-consistent 2-temperature radial model of plasma flow near Sgr A* that includes stellar winds, conduction, and relativistic effects, fitting multi-wavelength data.

Findings

Most gas outflows from the region, limiting accretion rate to below 1% of Bondi rate.

The X-ray brightness profile is too steep near the BH, indicating a synchrotron self-Compton point source.

The model successfully fits both X-ray and sub-mm emission from Sgr A*.

Abstract

We propose a 2-temperature radial dynamical model of plasma flow near Sgr A* and fit the bremsstrahlung emission to extensive quiescent X-Ray Chandra data. The model extends from several arcseconds to black hole (BH) gravitational radius, describing the outer accretion flow together with the infalling region. The model incorporates electron heat conduction, relativistic heat capacity of particles and feeding by stellar winds. Stellar winds from each star are considered separately as sources of mass, momentum and energy. Self-consistent search for the stagnation and sonic points is performed. Most of gas is found to outflow from the region. The accretion rate is limited to below 1% of Bondi rate due to the effect of thermal conduction enhanced by entropy production in a turbulent flow. The X-Ray brightness profile proves too steep near the BH, thus a synchrotron self-Compton point source is inferred with luminosity L=3x10^32erg/s. We fit the sub-mm emission from the inner flow, thus aiming at a single model of Sgr A* accretion suitable at any radius.