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تسجيل مستخدم جديدA broadband X-ray view of the NLSy1 1E 0754.6+392.8
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The soft X-ray band of many active galactic nuclei (AGNs) is affected by obscuration due to partially ionised matter crossing our line of sight. In this context, two past XMM-Newton observations (6 months apart) and a simultaneous NuSTAR-Swift ($sim$8 years later) exposure of the Narrow Line Seyfert 1 galaxy 1E 0754.6+392.8 revealed an intense and variable WA and hints of additional absorbers in the Fe K$alpha$ band. We present the first X-ray characterisation of this AGN discussing its broadband (0.3-79 keV) spectrum and temporal properties. We conduct a temporal and spectroscopic analysis on two $sim$10 ks (net exposure) XMM-Newton snapshots performed in April and October 2006. We also study the high energy behaviour of 1E 0754.6+392.8 modelling its broadband spectrum using simultaneous Swift-NuSTAR data. Both phenomenological and physically motivated models are tested. We find the presence of flux variability ($sim$150% and 30% for 0.3-2 and 2-10 keV bands, respectively) and spectral changes at months timescales ($DeltaGammasim$0.4). A reflection component that is consistent with being constant over years and arising from relatively cold material far from the central super massive black hole is detected. The main spectral feature shaping the 1E 0754.6+392.8 spectrum is a warm absorber. Such a component is persistent over the years and variability of its ionisation and column density is observed down on months in the ranges 3$times10^{22} rm cm^{-2}lesssim$ N$_{rm{H}}lesssim7.2times10^{22} rm cm^{-2}$ and 1.5 $lesssimlog(xi/{rm erg~s^{-1}~cm})lesssim$2.1. Despite the short exposures, we find possible evidence of two additional highly ionised and high-velocity outflow components in absorption. Longer exposures are mandatory in order to characterise the complex outflow in this AGN.
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