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تسجيل مستخدم جديدLocation and energetics of the ultra-fast outflow in PG 1448+273
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Ultra-fast outflows (UFOs) play a key role in the AGN feedback mechanism. It is therefore important to fully characterize their location and energetics. We study the UFO in the latest XMM-Newton archival observation of the NLSy1 galaxy PG 1448+273 by means of a novel modeling tool, that is, the Wind in the Ionized Nuclear Environment model (WINE). Our detection of the UFO in PG 1448+273 is very robust. The outflowing material is highly ionized, $logxi = 5.53_{-0.05}^{+0.04}$ erg s$^{-1}$ cm, has a large column density, $N_mathrm{H} = 4.5_{-1.1}^{+0.8} times 10^{23}$ cm$^{-2}$, is ejected with a maximum velocity $v_0 = 0.24^{+0.08}_{-0.06},c$ (90% c.l. errors), and attains an average velocity $v_mathrm{avg} = 0.152,c$. WINE succeeds remarkably well to constrain a launching radius of $r_0=77_{-19}^{+31} , r_mathrm{S}$ from the black hole. We also derive a lower limit on both the opening angle of the wind ($theta > 72^{circ}$) and the covering factor ($C_mathrm{f} > 0.69$). We find a mass outflow rate $dot{M}_mathrm{out}=0.65^{+0.44}_{-0.33},M_odot mathrm{yr}^{-1} = 2.0^{+1.3}_{-1.0}, dot{M}_mathrm{acc}$ and a large instantaneous outflow kinetic power $dot{E}_mathrm{out}=4.4^{+4.4}_{-3.6} times 10^{44}$ erg s$^{-1}$ = 24% $L_mathrm{bol}$ = 18% $L_mathrm{Edd}$ ($1 sigma$ errors). We find that a major error contribution on the energetics is due to $r_0$, stressing the importance of an accurate determination through a proper spectral modeling, as done with WINE. Using 20 Swift (UVOT and XRT) observations and the simultaneous OM data from XMM-Newton, we also find that $alpha_mathrm{ox}$ undergoes large variations, with a maximum excursion of $Deltaalpha_mathrm{ox} =-0.7$, after the UFO is detected, leading to a remarkable X-ray weakness. This may point towards a starving of the inner accretion disk due to the removal of matter through the wind.
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Relativistically blueshifted absorption features of highly ionised ions, the so-called ultra-fast outflows (UFOs), have been detected in the X-ray spectra of a number of accreting supermassive black holes. If these features truly originate from accre
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