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arXiv · 1002.2885

Flares from Sgr A* and their emission mechanism

K. Dodds-Eden·D. Porquet·G. Trap·E. Quataert·S. Gillessen·N. Grosso·R. Genzel·A. Goldwurm·F. Yusef-Zadeh·S. Trippe·H. Bartko·F. Eisenhauer·T. Ott·T. K. Fritz·O. Pfuhl
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Abstract

We summarize recent observations and modeling of the brightest Sgr A* flare to be observed simultaneously in (near)-infrared and X-rays to date. Trying to explain the spectral characteristics of this flare through inverse Compton mechanisms implies physical parameters that are unrealistic for Sgr A*. Instead, a "cooling break" synchrotron model provides a more feasible explanation for the X-ray emission. In a magnetic field of about 5-30 Gauss the X-ray emitting electrons cool very quickly on the typical dynamical timescale while the NIR-emitting electrons cool more slowly. This produces a spectral break in the model between NIR and X-ray wavelengths that can explain the differences in the observed spectral indices.

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K. Dodds-Eden, D. Porquet, G. Trap, E. Quataert, S. Gillessen, N. Grosso, R. Genzel, A. Goldwurm, F. Yusef-Zadeh, S. Trippe, H. Bartko, F. Eisenhauer, T. Ott, T. K. Fritz, O. Pfuhl. 2010-02-15. Flares from Sgr A* and their emission mechanism. https://arxiv.org/abs/1002.2885

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