An evolving hot spot orbiting around Sgr A*

Abstract

Here we report on recent near-infrared observations of the Sgr A* counterpart associated with the super-massive ~ 4x10^6 M_sun black hole at the Galactic Center. We find that the May 2007 flare shows the highest sub-flare contrast observed until now, as well as evidence for variations in the profile of consecutive sub-flares. We modeled the flare profile variations according to the elongation and change of the shape of a spot due to differential rotation within the accretion disk.

7 pages, 5 figures, contribution for the conference "The Universe under the Microscope" (AHAR 2008), to be published in Journal of Physics: Conference Series by Institute of Physics Publishing