Abstract
We have observed a bright flare of Sgr A* in the near-infrared with the adaptive optics-assisted integral-field spectrometer SINFONI. Within the uncertainties, the observed spectrum is featureless and can be described by a power law. Our data suggest that the spectral index is correlated with the instantaneous flux and that both quantities experience significant changes within less than 1 hour. We argue that the near-infrared flares from Sgr A* are due to synchrotron emission of transiently heated electrons, the emission being affected by orbital dynamics and synchrotron cooling, both acting on timescales of ≈20 minutes.
Original language | English (US) |
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Pages (from-to) | L163-L166 |
Journal | Astrophysical Journal |
Volume | 640 |
Issue number | 2 II |
DOIs | |
State | Published - Apr 1 2006 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
Keywords
- Black hole physics
- Galaxy: center
- Infrared: stars
- Techniques: spectroscopic