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تسجيل مستخدم جديدThe 1.5 Ms Observing Campaign on IRAS 13224-3809: X-ray Spectral Analysis I
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We present a detailed spectral analysis of the recent 1.5,Ms XMM-Newton observing campaign on the narrow line Seyfert 1 galaxy IRAS~13224$-$3809, taken simultaneously with 500,ks of NuSTAR data. The X-ray lightcurve shows three flux peaks, registering at about 100 times the minimum flux seen during the campaign, and rapid variability with a time scale of kiloseconds. The spectra are well fit with a primary powerlaw continuum, two relativistic-blurred reflection components from the inner accretion disk with very high iron abundance, and a simple blackbody-shaped model for the remaining soft excess. The spectral variability is dominated by the power law continuum from a corona region within a few gravitational radii from the black hole. Additionally, blueshifted Ne textsc{x}, Mg textsc{xii}, Si textsc{xiv} and S textsc{xvi} absorption lines are identified in the stacked low-flux spectrum, confirming the presence of a highly ionized outflow with velocity up to $v= 0.267$ and $0.225$,c. We fit the absorption features with texttt{xstar} models and find a relatively constant velocity outflow through the whole observation. Finally, we replace the texttt{bbody} and supersolar abundance reflection models by fitting the soft excess successfully with the extended reflection model texttt{relxillD}, which allows for higher densities than the standard texttt{relxill} model. This returns a disk electron density $n_{rm e}>10^{18.7}$,cm$^{-3}$ and lowers the iron abundance from $Z_{rm Fe}=24^{+3}_{-4}Z_odot$ with $n_{rm e}equiv10^{15}$,cm$^{-3}$ to $Z_{rm Fe}=6.6^{+0.8}_{-2.1}Z_odot$.
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