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arXiv · 0810.0138

An evolving hot spot orbiting around Sgr A*

M. Zamaninasab·A. Eckart·L. Meyer·R. Schoedel·M. Dovciak·V. Karas·D. Kunneriath·G. Witzel·R. Giessuebel·S. Koenig·C. Straubmeier·A. Zensus
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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.

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M. Zamaninasab, A. Eckart, L. Meyer, R. Schoedel, M. Dovciak, V. Karas, D. Kunneriath, G. Witzel, R. Giessuebel, S. Koenig, C. Straubmeier, A. Zensus. 2008-10-01. An evolving hot spot orbiting around Sgr A*. https://doi.org/10.1088/1742-6596/131/1/012008

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