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The Ultra Luminous Infrared Galaxy MKN 231: New clues from BeppoSAX and XMM-Newton

V. Braito·R. Della Ceca·E. Piconcelli·P. Severgnini·L. Bassani·M. Cappi·A. Franceschini·K. Iwasawa·G. Malaguti·P. Marziani·G. G. C. Palumbo·M. Persic·G. Risaliti·M. Salvati
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Abstract

We present BeppoSAX and XMM-Newton observations of MKN 231. These observations and in particular the BeppoSAX PDS data allowed us to unveil, for the first time, the highly absorbed (N$_H\sim 2\times10^{24}$ cm$^{-2}$) AGN component. We find that: a) the AGN powering MKN231 has an intrinsic 2-10 keV luminosity of $1^{+1}_{-0.5}\times 10^{44}$ erg/s; b) the strong starburst activity contributes significantly in the 0.1-10 keV energy range. We propose that the starburst activity strongly contributes to the far infrared luminosity of MKN 231; this is also suggested by the multiwavelength properties of MKN 231.

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V. Braito, R. Della Ceca, E. Piconcelli, P. Severgnini, L. Bassani, M. Cappi, A. Franceschini, K. Iwasawa, G. Malaguti, P. Marziani, G. G. C. Palumbo, M. Persic, G. Risaliti, M. Salvati. 2003-07-31. The Ultra Luminous Infrared Galaxy MKN 231: New clues from BeppoSAX and XMM-Newton. https://arxiv.org/abs/astro-ph/0307551

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