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Optical Continuum Variability of the Active Galaxy Mrk 279 - Implications for Different Accretion Regimes

Rumen Bachev·Anton Strigachev
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Abstract

We present results from a recent broad-band monitoring in optics of the Seyfert 1 type galaxy Mrk 279. We build and analyse the BVRI light curve covering a period of seven years (1995 - 2002). We also show some evidence for the existence of two different states in brightness and suggest, based on a modelling of the optical continuum, that these states may result from transition between a thin disk and an ADAF accretion modes. We assume that the short-term variability is due to a reprocessing of a variable X-ray emission from an inner ADAF part of the flow, while the long-term one may be a result from a change of the transition radius. Our tests show a good match with the observations for a reasonable set of accretion parameters, rather close to the ones, expected for Mrk 279.

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Rumen Bachev, Anton Strigachev. 2003-11-23. Optical Continuum Variability of the Active Galaxy Mrk 279 - Implications for Different Accretion Regimes. https://doi.org/10.1002/asna.200310177

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