Falcke, H.: The Jet Model for Sgr A*

The Jet Model for Sgr A*

Falcke H.1,2

1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany (hfalcke@mpifr-bonn.mpg.de)
2Steward Observatory, The University of Arizona, Tucson, AZ 85721

to appear in: "The Central Parsecs of the Galaxy", eds. H. Falcke, A. Cotera, W. Duschl, F. Melia, M. Rieke, ASP Conf. Series


In this paper the jet model for the supermassive black hole candidate Sgr A* in the Center of the Galaxy is reviewed. The most recent model, with a reduced set of parameters, is able to account for all major radio properties of the source: size, structure, flux density, and spectrum. The model requires a minimum jet power of ~1039 erg/sec and in a symbiotic jet/disk system implies a minimum accretion rate of a few times 10-8 Mo/yr for a radio loud jet or 10-5 Mo/yr for a radio quiet jet. Low near-infrared limits on the Sgr A* flux then imply that the accretion flow onto the central black hole must be radiatively deficient, but most likely has a high viscosity. Within the jet model the high-frequency part of the Sgr A* spectrum is self-consistently explained as the nozzle of the outflow. In a symbiotic model this innermost region of the jet could possibly be identified with the innermost region of an advection dominated accretion disk, a Bondi-Hoyle accretion flow, or any other type of underluminous accretion process. The compact nozzle region is of particular importance since it can be used as a background photon source against which the central black hole could be directly imaged with future mm-VLBI experiments.

Paper: Available in full length as PostScript and LaTex Format.

Other publications can be found here.

Questions: Heino Falcke, hfalcke@mpifr-bonn.mpg.de