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Arp 299: a second merging system with two active nuclei?

L. Ballo·V. Braito·R. Della Ceca·L. Maraschi·F. Tavecchio·M. Dadina
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Abstract

Recent BeppoSAX observations of Arp 299, a powerful far-IR merging starburst system composed of IC 694 and NGC 3690, clearly unveiled for the first time in this system the presence of a strongly absorbed active galactic nucleus (AGN). However the system was not spatially resolved by BeppoSAX. Here we present the analysis of archival Chandra and (for the first time) XMM-Newton observations, which allow us to disentangle the X-ray emission of the two galaxies. The detection of a strong 6.4 keV line in NGC 3690 clearly demonstrates the existence of an AGN in this galaxy, while the presence of a strong 6.7 keV Fe-Kalpha line in the spectrum of IC 694 suggests that also this nucleus might harbor an AGN. This would be the second discovery of two AGNs in a merging system after NGC 6240.

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L. Ballo, V. Braito, R. Della Ceca, L. Maraschi, F. Tavecchio, M. Dadina. 2003-11-07. Arp 299: a second merging system with two active nuclei?. https://doi.org/10.1086/379887

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