相关论文: Broad iron L-line and X-ray reverberation in 1H070…
We report results obtained from a systematic analysis of X-ray lags in a sample of black hole X-ray binaries, with the aim of assessing the presence of reverberation lags and studying their evolution during outburst. We used XMM-Newton and…
We present a systematic analysis of the X-ray spectral properties of a sample of 22 ``narrow-line'' Seyfert 1 galaxies for which data are available from the ASCA public archive. Many of these sources, which were selected on the basis of…
XMM-Newton observations of the bright Seyfert 1.9 galaxy MCG-5-23-16 have revealed a broad FeKalpha emission line which is nearly symmetric in contrast to the broad and red-shifted asymmetric FeKalpha line sometimes observed from Seyfert 1…
X-rays illuminating the accretion disc in active galactic nuclei give rise to an iron K line and its associated reflection spectrum which are lagged behind the continuum variability by the light-travel time from the source to the disc. The…
ASCA X-ray spectral analysis of the Seyfert 2 galaxy IRAS 04575-7537 is presented. The main result is the presence of a significant iron edge at a rest energy of 7.13^+0.21_-0.16 keV. The spectrum is flat (Gamma = 1.5) with a substantial…
We present the analysis of four XMM-Newton observations of the narrow-line quasar PG 1543+489 at z=0.400 carried out over a rest-frame time-scale of about three years. The X-ray spectrum is characterized by a broad, relativistic iron…
In the past five years, a flurry of X-ray reverberation lag measurements of accreting supermassive black holes have been made using the XMM-Newton telescope in the 0.3-10 keV energy range. In this work, we use the NuSTAR telescope to extend…
We present first results from a 325 ks observation of the Seyfert 1 galaxy MCG-6-30-15 with XMM-Newton and BeppoSAX. The strong, broad, skewed iron line is clearly detected and is well characterised by a steep emissivity profile within 6r_g…
Narrow-line Seyfert\,1 galaxies (NLS1s) with very small broad-line widths (say, FWHM(\hb) $\la $ 1200\,\kms) represent the extreme type of Seyfert\,1 galaxies that have small black hole masses (\mbh) and/or high Eddington ratios (\redd).…
The Narrow Line Seyfert 1 galaxy NGC4051 shows unusual low flux states, lasting several months, when the 2-10 keV X-ray spectrum becomes unusually hard (photon index<1) while the spectrum at lower X-ray energies is dominated by a large soft…
We present the results of the analysis of an archival 15 ks XMM-Newton observation of the nearby (z=0.057) radio-loud source 3C445, optically classified as a Broad-Line Radio Galaxy. While the RGS data are of insufficient quality to allow a…
In this paper we report on the first simultaneous optical and X-ray (Beppo-SAX) observations of the radio-quiet AGN 1H0419-577. The optical spectrum clearly leads us to classify this source as a Seyfert 1. The X-ray spectrum is, however,…
We present results from the spectral analysis of the Seyfert 1.9 galaxy MCG-5-23-16, based on ASCA, BeppoSAX, Chandra and XMM-Newton observations. The spectrum of this object shows a complex iron Kalpha emission line, which is best modeled…
An intrinsically narrow line emitted by an accretion disk around a black hole appears broadened and skewed as a result of the Doppler effect and gravitational redshift. The fluorescent iron line in the X-ray band at 6.4-6.9keV is the…
We report on a 151 ks net exposure Suzaku observation of the Narrow Line Seyfert 1 galaxy Mrk 335. The 0.5-40 keV spectrum contains a broad Fe line, a strong soft excess below about 2 keV and a Compton hump around 20-30 keV. We find that a…
We investigate the origin of the broad absorption features detected near 1-1.4 keV in several Narrow Line Seyfert 1 galaxies, by modelling the absorbing medium with various physical parameters, using the ionization code PEGAS. The observed…
A fraction of active galactic nuclei (AGN) exhibit dramatic variability, which is observed on timescales down to minutes in the X-ray band. We introduce the case study of 1H 1934-063 (z = 0.0102), a Narrow-line Seyfert 1 (NLS1) among the…
XMM-Newton observations of type I AGN are presented. The properties of the iron K emission line are reviewed, the majority of AGN observed by XMM-Newton show narrow, unresolved (by XMM) iron lines at 6.4 keV from cold matter that must…
The BeppoSAX observations of the bright Narrow-Line Seyfert 1 galaxy Ark 564 are presented along with a high quality optical spectrum taken at the 1.5m telescope at La Silla. The 0.1-10 keV X-ray spectrum is characterized by a strong soft…
We present new broadband X-ray observations of the type-I Seyfert galaxy IRAS 09149-6206, taken in 2018 with $XMM$-$Newton$, $NuSTAR$ and $Swift$. The source is highly complex, showing a classic 'warm' X-ray absorber, additional absorption…