相关论文: Variable oxygen emission from the accretion disk o…

We present a XMM-Newton observation of Markarian 304, a Seyfert 1 galaxy at z = 0.066. The EPIC data show that MKN 304 is affected by heavy (Nh ~10^{23} cm{-2}) obscuration due to ionized gas. A two-phase warm absorber provides an adequate…

Competing models for broad spectral features in the soft X-ray spectrum of the Seyfert I galaxy Mrk766 are tested against data from a 130 ks XMM-Newton observation. A model including relativistically broadened Ly-alpha emission lines of…

A 100ks XMM-Newton observation of the nearby Seyfert 2 galaxy Mrk 3 offers a unique opportunity to explore the complexity of its X-ray spectrum. We find the \~3-8 keV continuum to be dominated by reflection from cold matter, with…

Complex Fe-K emission/absorption line features are commonly observed in the 6--11 keV band from Active Galactic Nuclei (AGN). These features are formed in various physical components surrounding the black holes. The Narrow-Line Seyfert 1…

We examine a 200 ks XMM-Newton observation of the narrow-line Seyfert 1 galaxy Mrk 493. The active galaxy was half as bright as in a previous 2003 snapshot observation and the current lower flux enables a study of the putative reflection…

Aims: We analyse a long XMM-Newton spectrum of the narrow-line Seyfert 1 galaxy Mrk 766, using the marked spectral variability on timescales >20ks to separate components in the X-ray spectrum. Methods: Principal components analysis is used…

Detections of $z \approx$ 0 oxygen absorption and emission lines indicate the Milky Way hosts a hot ($\sim 10^6$ K), low-density plasma extending $\gtrsim$50 kpc into the Mily Way's halo. Current X-ray telescopes cannot resolve the line…

The XMM-Newton observation of the optically Type 1 AGN AXJ0447-0627 (z=0.214) unambiguously reveals a complex, bright and prominent set of lines in the 4-8 keV rest frame energy range. Although, from a phenomenological point of view, the…

We present the results of a ~160 ks-long XMM-Newton observation of the Seyfert 1 galaxy Mrk 279. The spectrum shows evidence of both broad and narrow emission features. The Fe K alpha line may be equally well explained by a single broad…

We present a spectral variability study of the XMM-Newton and Suzaku observations of one of the most extreme Narrow Line Seyfert 1 galaxies, IRAS13224-3809. The X-ray spectrum is characterized by two main peculiar features, i) a strong soft…

We analyse the spectra of the archival XMM-Newton data of the Seyfert 1 AGN Zw 229.015 in the energy range $0.3 - 10.0$ keV. When fitted with a simple power-law, the spectrum shows signatures of weak soft excess below 1.0 keV. We find that…

We performed a detailed spectral and timing analysis of a Seyfert 1 galaxy Mrk 509 using data from the Neil Gehrels Swift observatory that spanned over ~13 years between 2006 and 2019. To study the variability properties from the optical/UV…

There is growing evidence for the presence of blueshifted Fe K absorption lines in a number of radio-quiet AGNs and QSOs. These may be fundamental to probe flow dynamics near supermassive black holes. Here we aim at verifying and better…

We model the broad emission lines present in the optical, UV and X-ray spectra of Mrk 509, a bright type 1 Seyfert galaxy. The broad lines were simultaneously observed during a large multiwavelength campaign, using the XMM-Newton-OM for the…

We present the second XMM-Newton observation (85 ks) of the narrow-line Seyfert 1 galaxy (NLS1) I Zw 1 and describe its mean spectral and timing characteristics. On average, I Zw 1 is ~35 per cent dimmer in 2005 than in the shorter (20 ks)…

In the recent literature on AGNs it has been often reported that spectra of Seyfert 1 Galaxies show resonant absorption lines of Fe K which are redshifted from the rest frame position. Such lines are often found with marginal significance…

We observed the Galactic black hole Cygnus X-1 with the Chandra High Energy Transmission Grating Spectrometer for 30 kiloseconds on 4 January, 2001. The source was in an intermediate state, with a flux that was approximately twice that…

Iron line emission is common in the X-ray spectra of accreting black holes. When the line emission is broad or variable then it is likely to originate from close to the black hole. X-ray irradiation of the accretion flow by the power-law…

We present XMM-Newton, NuSTAR, Swift and Hubble Space Telescope observations of the Narrow-line Seyfert 1 galaxy Mrk 335 in a protracted low state in 2018 and 2019. The X-ray flux is at the lowest level so far observed, and the extremely…

The narrow line Seyfert 1 (NLS1) IRAS 13224-3809 is the most X-ray variable active galactic nucleus (AGN), exhibiting 0.3-10 keV flux changes of over an order of magnitude within an hour. We report on the results of the 1.5 Ms 2016…