The Galactic Center - an AGN on a starvation diet

The Galactic Center shows evidence for the presence of three important AGN ingredients: a Black Hole ($M_{\bullet }\sim {10}^6{M}_{\odot }$), an accretion disk (${10}^{-8.5}-{10}^{-7}{M}_{\odot }\mathrm{/}\mathrm{y}\mathrm{r}$) and a powerful jet (jet power $\ge$ 10% disk luminosity). However, the degree of activity is very low and can barely account for the energetics of the whole central region. Neverthelss, in the very inner arsecond the central engine becomes dominant and provides an interesting laboratory for the physics of central engines (Black Holes) in galactic nuclei. We therefore give an overall picture of the central arcsecond where we link the radio emission and the heating of the ambient medium to a weakly accreting disk surrounding a massive Black Hole. <<<To appear in the conference proceedings “Mass Transfer Induced Activity in Galaxies”, Lexington 93, I. Shlosman (ed.)>>>