Unified Accretion Model for Sgr A*
Abstract
We propose a single dynamic model for Sgr A* accretion spanning a factor of a million in radius from the stellar winds feeding region at arcsecond scales down to the plunging region onto a Kerr black hole (BH). The outer accretion flow incorporates injection of mass and energy from individual stars and thermal conduction, which inhibits accretion. The inner region of the flow is modeled using non-radiating 3D GRMHD simulations for a set of BH spins. The smooth connection is made between the outer flow and the inner flow. The surface brightness profile of the extended X-Ray source fits well 1Ms Chandra observations of Sgr A*. The polarized GR ray tracing of cyclo-synchrotron emission is performed to quantify the emission of the inner flow. The parameter space of BH spin, inclination and model variables is explored in order to fit the observed sub-mm spectrum as well as linear and circular polarization fractions found by SMA. The polarized images are calculated and their sizes are related to the observed VLBI correlated flux. This work is partially supported by NASA Earth and Space Science Fellowship.
- Publication:
-
American Astronomical Society Meeting Abstracts #215
- Pub Date:
- January 2010
- Bibcode:
- 2010AAS...21531003S