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A dual emission mechanism in Sgr A*/L' ?

Yann Clénet·Daniel Rouan·Damien Gratadour·Olivier Marco·Pierre Léna·Nancy Ageorges·Eric Gendron
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Abstract

We have collected in 2004 adaptive optics corrected L' images of the Galactic Center region with NAOS-CONICA at VLT. A strong variability was observed as well as a correlation between the photocenter positions and fluxes of the L'-band counterpart of Sgr A*. It is interpreted as the combined emission of a point-like flaring source at the position of Sgr A*/IR itself and an extended dust structure, 75 mas south west of Sgr A*/IR, which we name Sgr A*-f. We examine the different possible mechanisms to explain this dual Sgr A* L' emission and conclude it is likely a flaring emission associated to energetic events in the close environment of the black hole plus a quiescent emission resulting from the collision of Sgr A*-f by a jet from Sgr A*.

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Yann Clénet, Daniel Rouan, Damien Gratadour, Olivier Marco, Pierre Léna, Nancy Ageorges, Eric Gendron. 2005-07-05. A dual emission mechanism in Sgr A*/L' ?. https://doi.org/10.1051/0004-6361%3A200500146

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