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Register a new userA 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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We present the X-ray properties of the Teacup AGN (SDSS J1430+1339), a $z=0.085$ type 2 quasar which is interacting dramatically with its host galaxy. Spectral modelling of the central quasar reveals a powerful, highly obscured AGN with a column density of $N_{rm H}=(4.2$-$6.5)times 10^{23}$ cm$^{-2}$ and an intrinsic luminosity of $L_{rm 2mbox{-}10,keV}=(0.8$-$1.4)times 10^{44}$ erg s$^{-1}$. The current high bolometric luminosity inferred ($L_{rm bol}approx 10^{45}$-$10^{46}$ erg s$^{-1}$) has ramifications for previous interpretations of the Teacup as a fading/dying quasar. High resolution Chandra imaging data reveal a $approx 10$ kpc loop of X-ray emission, co-spatial with the eastern bubble previously identified in luminous radio and ionised gas (e.g., [OIII] line) emission. The X-ray emission from this structure is in good agreement with a shocked thermal gas, with $T=(4$-$8)times 10^{6}$ K, and there is evidence for an additional hot component with $Tgtrsim 3times 10^{7}$ K. Although the Teacup is a radiatively dominated AGN, the estimated ratio between the bubble power and the X-ray luminosity is in remarkable agreement with observations of ellipticals, groups, and clusters of galaxies undergoing AGN feedback.
We present joint textit{XMM-Newton} and textit{NuSTAR} observations of the `bare narrow line Seyfert 1 Ton S180 ($z=0.062$), carried out in 2016 and providing the first hard X-ray view of this luminous galaxy. We find that the 0.4--30 keV band cannot be self-consistently reproduced by relativistic reflection models, which fail to account simultaneously for the soft and hard X-ray emission. The smooth soft excess prefers extreme blurring parameters, confirmed by the nearly featureless nature of the RGS spectrum, while the moderately broad Fe K line and the modest hard excess above 10 keV appear to arise in a milder gravity regime. By allowing a different origin of the soft excess, the broadband X-ray spectrum and overall spectral energy distribution (SED) are well explained by a combination of: (a) direct thermal emission from the accretion disc, dominating from the optical to the far/extreme UV; (b) Comptonization of seed disc photons by a warm ($kT_{rm e}sim0.3$ keV) and optically thick ($tausim10$) corona, mostly contributing to the soft X-rays; (c) Comptonization by a standard hot ($kT_{rm e} gtrsim 100$ keV) and optically thin ($tau<0.5$) corona, responsible for the primary X-ray continuum; and (d) reflection from the mid/outer part of the disc. The two coronae are suggested to be rather compact, with $R_{rm hot} lesssim R_{rm warm} lesssim 10$ R$_{rm g}$. Our SED analysis implies that Ton S180 accretes at super-Eddington rates. This is a key condition for the launch of a wind, marginal (i.e., 3.1$sigma$ significance) evidence of which is indeed found in the RGS spectrum.
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