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The BeppoSAX spectrum of the composite galaxy Mrk609

A. Pappa·I. Georgantopoulos·M. Ward·A. L. Zezas
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Abstract

We present Bepposax observations of the starburst/Seyfert composite galaxy Mrk609. This enigmatic object has an optical spectrum dominated by the features of starburst galaxies, yet its X-ray luminosity (6.3$\times10^{42}$\lunits) is typical of an AGN. The X-ray spectrum of Mrk609 can be parameterised by a single power-law model with a photon index $Γ\sim1.6\pm0.1$ and no evidence for significant absorption above the Galactic value. Long term variability in both the 0.1-2 keV and 2-10 keV energy bands is detected, again suggesting that the X-ray emission is dominated by an AGN. The observed broad Ha component is a factor of 40 below that predicted by the X-ray flux implying a deficit of ionizing UV photons.

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A. Pappa, I. Georgantopoulos, M. Ward, A. L. Zezas. 2002-04-30. The BeppoSAX spectrum of the composite galaxy Mrk609. https://doi.org/10.1046/j.1365-8711.2002.05629.x

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