相关论文: The Additional Line Component within the Iron K\al…
Iron K-alpha lines are key diagnostics of the central regions of AGN. Their profiles indicate that they are formed deep in the potential well of the central black hole, where extreme broadening and red shift occur. The profiles are most…
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…
We report on the variability of the iron K emission line in the Seyfert 1 galaxy MCG--6-30-15 during a four-day ASCA observation. The line consists of a narrow core at an energy of about 6.4 keV, and a broad red wing extending to below 5…
We present a high resolution X-ray spectrum of the iron K bandpass in MCG-6-30-15 based on a 522 ksec observation with Chandra's High Energy Transmission Grating Spectrometer. The Chandra spectrum is consistent with the presence of a…
We report results on the broad iron emission line of the Seyfert galaxy MCG-6-30-15, obtained from the second long ASCA observation in 1997. The time-averaged profile of the broad line is very similar to that seen with ASCA in 1994, so…
We confirm the detection of the relativistically broadened iron K-alpha emission at 6.4 keV with simultaneous Chandra HETGS and RXTE PCA observations. Heavily binned HETGS data show a disk line profile with parameters very similar to those…
Initial results on the iron K-shell line and reflection component in several AGN observed as part of the Suzaku Guaranteed time program are reviewed. This paper discusses a small sample of Compton-thin Seyferts observed to date with Suzaku;…
We use the method of Press, Rybicki & Hewitt (1992) to search for time lags and time leads between different energy bands of the RXTE data for MCG-6-30-15. We tailor our search in order to probe any reverberation signatures of the…
GX 339-4 was regularly monitored with RXTE during a period (in 1999) when its X-ray flux decreased significantly (from 4.2$\times 10^{-10}$ erg cm$^{-2} s^{-1}$ to 7.6$\times 10^{-12}$ erg cm$^{-2}$s$^{-1}$ in the 3--20 keV band), as the…
We have compared the 2001 XMM-Newton spectra of the stellar mass black hole binary XTE J1650-500 and the active galaxy MGC-6-30-15, focusing on the broad, excess emission features at ~4--7 keV displayed by both sources. Such features are…
The observed iron K-alpha fluorescence lines in Seyfert-1 galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the emission. Here we present an analysis of the geometrical and kinematic…
Recent X-ray spectroscopy made with ASCA have shown broad, skewed iron line emission from Seyfert-1 galaxies. The large extent of the red tail allows probing of the innermost regions of the black hole's accretion disc. A model of line…
We present results of new ASCA observations of the low-luminosity AGN (LLAGN) NGC 4579 obtained on 1998 December 18 and 28, and we report on detection of variability of an iron K emission line. The X-ray luminosities in the 2--10 keV band…
XMM-Newton observations of the low luminosity, radio-quiet quasar Markarian 205 have revealed a unique iron K emission line profile. In marked contrast to the broad and redshifted iron K line commonly seen in ASCA observations of Seyfert 1…
Recent X-ray observations have shown evidence for exceptionally broad and skewed iron K alpha emission lines from several accreting black hole systems. The lines are assumed to be due to fluorescence of the accretion disk illuminated by a…
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 the results from a large observational campaign on the bare Seyfert galaxy Ark 120, jointly carried out in 2014 with XMM-Newton, Chandra, and NuSTAR. The fortunate line of sight to this source, devoid of any significant…
Petrucci et al. (2002; hereafter P02) have reported extraordinary behaviour of the iron K alpha line in the type 1 AGN Mrk 841. At the XMM-Newton/EPIC resolution, a narrow line was observed in a short observation, which then apparently…
The spectrum and variability of the Seyfert galaxy MCG-6-30-15 can be decomposed into two apparently disconnected components: a highly variable power law and an almost constant component which contains a broad and strong iron line. We…
The bright Seyfert 1 galaxy MCG-6-30-15 has provided some of the best evidence to date for the existence of supermassive black holes in active galactic nuclei. Observations with ASCA revealed an X-ray iron line profile shaped by strong…