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تسجيل مستخدم جديدMulti-wavelength Campaign on NGC 7469 VI. Photoionisation Modelling of the Emission Line Regions and the Warm Absorber
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Aims. We aim to investigate and characterise the photoionised X-ray emission line regions within NGC 7469. Methods. We apply the photoionisation model, PION, within the spectral fitting code SPEX to analyse the 640 ks RGS spectrum of NGC 7469 gathered during an XMM-Newton observing campaign in 2015. Results. We find the emission line region in NGC 7469 to be multiphased, consisting of two narrow components with ionisation parameters of $log xi = 0.4$ and 1.6. A third, broad emission component, with a broadening velocity of $v_b sim 1400$ km stextsuperscript{-1} and an outflow velocity of $v_{out} sim -4500$ km stextsuperscript{-1}, is required to fit the residuals in the O VII triplet, at around 22 AA. Assuming a volume filling factor of 0.1, the lower distance limits of the narrow emission line region components are estimated for the first time at 2.6 and 2.5 pc from the central black hole, whereas the broad component has an estimated lower bound distance between 0.004 to 0.03 pc, depending on the assumed plasma parameters. The collisionally ionised plasma from the star burst region in NGC 7469 has a plasma temperature of 0.32 keV and outflow velocity of $-280$ km stextsuperscript{-1}, consistent with previous results in this campaign. In addition, we model the photoionised plasma of the warm absorber (WA) in NGC 7469, and find that it consists of three photoionised phases, with different values of $xi$, $N_H$ and $v_{out}$. The upper bound distances of these WA components are 1.9, 0.3 and 0.6 pc, respectively, consistent with archival results. Conclusions. The environment of NGC 7469 is a complex mix of plasma winds absorbing and emitting X-rays. We find the picture painted by our results can be attributed to line emitting plasma located at distances ranging from near the black hole to the torus and beyond the ionised outflows.
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We conducted a multi-wavelength six-month campaign to observe the Seyfert galaxy NGC~7469, using the space-based observatories textit{HST}, textit{Swift}, textit{XMM-Newton} and textit{NuSTAR}. Here we report the results of the spectral analysis of t
he 7 simultaneous textit{XMM-Newton} and textit{NuSTAR} observations. The sources shows significant flux variability within each observation, but the average flux is less variable among the different pointings of our campaign. Our spectral analysis reveals a prominent narrow neutral ion{Fe} K$alpha$ emission line in all the spectra, with weaker contributions from Fe K$beta$, neutral Ni K$alpha$ and ionised iron. We find no evidence for variability or relativistic effects acting on the emission lines, which indicates that they originate from distant material. Analysing jointly textit{XMM-Newton} and textit{NuSTAR} data a constant photon index is found ($Gamma$=$1.78pm0.02$), together with a high energy cut-off $E_{rm{cut}}=170^{+60}_{-40}$ keV. Adopting a self-consistent Comptonization model, these values correspond to an average coronal electron temperature of kT=$45^{+15}_{-12}$ keV and, assuming a spherical geometry, an optical depth $tau=2.6pm0.9$. The reflection component is consistent with being constant, with a reflection fraction in the range $R=0.3-0.6$. A prominent soft excess dominates the spectra below 4 keV. This is best fit with a second Comptonization component, arising from a virg{warm corona} with an average $kT=0.67pm0.03$ keV and a corresponding optical depth $tau=9.2pm0.2$.
We investigate the photoionised X-ray emission line regions (ELRs) within the Seyfert 2 galaxy NGC 1068, to determine if there are any characteristic changes between observations taken fourteen years apart. We compare XMM-Newton observations collecte
d in 2000 and 2014, simultaneously fitting the reflection grating spectrometer (RGS) and EPIC-pn spectra of each epoch, for the first time, with the photoionisation model, PION, in SPEX. We find that four PION components are required to fit the majority of the emission lines in the spectra of NGC 1068, with $log xi=1-4$, $log N_H>26 m^{-2}$, and $v_{out}=-100$ to $-600 kms^{-1}$ for both epochs. Comparing the ionisation state of the components shows almost no difference between the two epochs, while there is an increase in the total column density. To estimate the locations of these plasma regions from the central black hole we compare distance methods, excluding the variability arguments as there is no spectral change between observations. Although the methods are unable to constrain the distances, the locations are consistent with the narrow line region, with the possibility of the higher ionised component being part of the broad line region, but we cannot conclude this for certain. In addition, we find evidence for emission from collisionally ionised plasma, while previous analysis had suggested that collisional plasma emission was unlikely. However, although PION is unable to account for the FeXVII emission lines at 15 and 17 AA, we do not rule out that photoexcitation is a valid processes to produce these lines too. NGC 1068 has not changed, both in terms of the observed spectra or from our modelling, within the 14 year time period between observations. This suggests that the ELRs are fairly static relative to the 14 year time frame between observations, or there is no dramatic change in the black hole variability.
We investigate the physical structure of the AGN wind in the Seyfert-1 galaxy NGC 7469 through high-resolution X-ray spectroscopy with Chandra HETGS and photoionisation modelling. Contemporaneous data from Chandra, HST, and Swift are used to model th
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Aims. Our aim is to determine the distance of the UV outflow components from the central source, their abundances and total column density, and the mechanism responsible for their observed absorption variability. Methods. We studied the UV spectra
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