Falcke et al.: Sgr A*: observations, models, event horizon

Sgr A*: observations, models, and imaging of the event horizon with VLBI

Heino Falcke1, Sera Markoff1, Peter L. Biermann1, Thomas P. Krichbaum1, Fulvio Melia2, Eric Agol3, Geoffrey Bower4

1Max-Planck-Institut für Radioastronomie, Auf den Hügel 69, D-53121 Bonn, Germany (hfalcke)
2Physics Department and Steward Observatory, The University of Arizona, Tucson, AZ 85721
3Theoretical Astrophysics, Caltech MS 130-33, 1200 E. California Blvd., Pasadena, CA 91125
4Radio Astronomy Laboratory, University of California, Berkeley, CA 94720

in: "Galaxies and their Constituents at the Highest Angular Resolution", IAU Symp. 205, Eds. Richard Schilizzi, Stuart Vogel, Francesco Paresce, Martin Elvis, Am. Soc. Pacific


We show and discuss results and prospects of high-resolution imaging of the supermassive black hole candidate Sgr A*. We also briefly review the latest observational and theoretical progress for this source. The latest millimeter-VLBI observations show compact radio emission from within a region of about 15 Schwarzschild radii. This compact component is most likely responsible for the so-called sub-mm bump in the spectrum and perhaps even for the recently discovered circular polarization discovered up to 43 GHz and some X-ray emission through synchrotron self-Compton emission. Most importantly, however, the sub-mm emission from Sgr A* opens the door to observe, for the first time, the event horizon of a black hole directly with VLBI at sub-mm wavelengths.

Paper: Available in PostScript and (AAS)LaTex. Please send an email request to hfalcke@mpifr-bonn.mpg.de for a preprint.

Other publications can be found here.

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