Context : We discuss here a long Suzaku observation of IRAS 19254-7245 ( also known as the Superantennae ) , one of the brightest and well studied Ultra Luminous Infrared Galaxies in the local Universe . This long observation provided the first detection of IRAS 19254-7245 above 10 keV , and measured a 15–30 keV flux of \sim 5 \times 10 ^ { -12 } erg cm ^ { -2 } s ^ { -1 } .
The detection above 10 keV has allowed us to unveil , for the first time , the intrinsic luminosity of the AGN hosted in IRAS 19254-7245 , which is strongly absorbed ( N _ { \mathrm { H } } \sim 3 \times 10 ^ { 24 } cm ^ { -2 } ) and has an intrinsic luminosity in the QSO regime ( L ( 2–10 keV ) \sim 3 \times 10 ^ { 44 } erg s ^ { -1 } ) . The 2– 10 keV spectrum of IRAS 19254-7245 is remarkably hard ( \Gamma \sim 1.2 ) , and presents a strong iron line ( EW \sim 0.7 keV ) , clearly suggesting that below 10 keV we are seeing only reprocessed radiation .
Since the energy of the Fe K emission is found to be at \sim 6.7 keV , consistent with He-like Fe , and its EW is too high to be explained in a starburst dominated scenario , we suggest that the 2–10 keV emission of IRAS 19254-7245 is dominated by reflection/scattering from highly ionized matter .
Indeed , within this latter scenario we found that the photon index of the illuminating source is \Gamma = 1.87 ^ { +0.11 } _ { -0.28 } , in excellent agreement with the mean value found for radio quiet unobscured AGN .

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