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arXiv · 0704.3065

XMM-Newton view of galaxy pairs: activation of quiescent black holes?

E. Jimenez-Bailon·N. Loiseau·M. Guainazzi·G. Matt·D. Rosa-Gonzalez·E. Piconcelli·M. Santos-Lleo
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Abstract

We report on XMM-Newton observations of three nearby galaxy pairs, AM0707-273, AM1211-465, and AM2040-674. All six galaxies were previously classified as HII galaxies based on optical and IR spectroscopic analysis. All galaxies were detected with XMM-Newton and each member was isolated and analyzed independently. The X-ray spectra reveal strong evidence of AGN activity in the NE member of AM1211-465 pair. We measured a luminosity of 1.94(+0.11/-0.15)x10^42 erg/s in the 2-10 keV band and the presence of a neutral FeK_alpha line with a confidence level of 98.8%. The high nH value, 2.2+/-0.2x10^22 cm^-2, would explain the misclassification of the source. Marginal evidence of AGN nature was found in the X-ray spectra of AM1211-465SW and AM0707-273E. The X-ray emission of the three remaining galaxies can be explained by starburst activity.

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E. Jimenez-Bailon, N. Loiseau, M. Guainazzi, G. Matt, D. Rosa-Gonzalez, E. Piconcelli, M. Santos-Lleo. 2007-04-23. XMM-Newton view of galaxy pairs: activation of quiescent black holes?. https://doi.org/10.1051/0004-6361:20066761

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