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The XMM-Newton and BeppoSAX view of the Ultra Luminous Infrared Galaxy MKN 231

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 discuss XMM-Newton and BeppoSAX observations of MKN 231, the lowest-redshift Broad Absorption Line (BAL) QSO known so far and one of the best-studied Ultra Luminous Infrared Galaxies. By combining the XMM-Newton spectral resolution and the high-energy bandpass of BeppoSAX we have been able to study in more detail than previously possible its 0.2--50 keV spectral properties. The BeppoSAX PDS data unveiled, for the first time, a highly absorbed ($N_H\sim 2\times 10^{24}$cm$^{-2}$) power-law component. We find that: a) below 10 keV we are seeing only reprocessed radiation through reflection and/or scattering; b) the intrinsic 2-10 keV luminosity of MKN 231 is $1^{+1.0}_{-0.5} \times 10^{44}$ ergs s$^{-1}$, i.e. more than an order of magnitude greater than previous measurements; c) the starburst activity significantly contributes to the soft ($E<2$ keV) X-ray emission.

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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. 2004-02-10. The XMM-Newton and BeppoSAX view of the Ultra Luminous Infrared Galaxy MKN 231. https://doi.org/10.1051/0004-6361%3A20040061

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