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The location and kinematics of the coronal-line emitting regions in AGN
J. R. Mullaney, M. J. Ward, C. Done +2
We use the photoionisation code Cloudy to determine both the location and the kinematics of the optical forbidden, high ionisation line (hereafter, FHIL) emitting gas in the narrow…
The impact of accretion disk winds on the X-ray spectrum of AGN: Part 2 - XSCORT + Hydrodynamic Simulations
N. J. Schurch, C. Done, D. Proga
abridged: We use XSCORT, together with the hydrodynamic accretion disc wind simulation from Proga & Kallman (2004), to calculate the impact that the accretion disk wind has on the…
Reprocessing of X-rays in the outer accretion disc of the black hole binary XTE J1817--330
Marek Gierlinski, Chris Done, Kim Page
We build a simple model of the optical/UV emission from irradiation of the outer disc by the inner disc and coronal emission in black hole binaries. We apply this to the broadband…
RE J1034+396: The origin of the soft X-ray excess and QPO
Matthew Middleton, Chris Done, Martin Ward +2
The X-ray quasi-periodic oscillation (QPO) seen in RE J1034+396 is so far unique amongst AGN. Here we look at the another unique feature of RE J1034+396, namely its huge soft X-ray…
A ~1-hour X-ray periodicity in an active galaxy RE J1034+396
Marek Gierlinski, Matthew Middleton, Martin Ward +1
Active galactic nuclei and quasars are thought to be scaled up versions of Galactic black hole binaries, powered by accretion onto supermassive black holes with masses of 10^6-10^9…
Angular Momentum Transport in Accretion Disks and its Implications for Spin Estimates in Black Hole Binaries
Chris Done, Shane W. Davis
The accretion flow in the disk dominated state of black hole binaries has peak temperature and luminosity which vary together in such a way as to indicate an approximately constant…
X-ray irradiation in XTE J1817-330 and the inner radius of the truncated disc in the hard state
Marek Gierlinski, Chris Done, Kim Page
The key aspect of the very successful truncated disc model for the low/hard X-ray spectral state in black hole binaries is that the geometrically thin disc recedes back from the la…
Suzaku Results on Cygnus X-1 in the Low/Hard State
Kazuo Makishima, Hiromitsu Takahashi, Shin'ya Yamada +9
The black-hole binary Cygnus X-1 was observed for 17 ks with the Suzaku X-ray observatory in 2005 October, while it was in a low/hard state with a 0.7-300 keV luminosity of 4.6 x 1…
A Deep 0.3-10 keV Spectrum of the HO Maser Galaxy IC 2560
Avanti Tilak, Lincoln Greenhill, Chris Done +1
We present a new XMM-Newton spectrum of the Seyfert 2 nucleus of IC 2560, which hosts HO maser emission from an inclined Keplerian accretion disk. The X-ray spectrum shows so…
On why the Iron K-shell absorption in AGN is not a signature of the local Warm/Hot Intergalactic Medium
James Reeves, Chris Done, Ken Pounds +3
We present a comparison between the 2001 XMM-Newton and 2005 Suzaku observations of the quasar, PG1211+143 at z=0.0809. Variability is observed in the 7 keV iron K-shell absorption…
High Energy spectra of Seyferts and Unification schemes
Matthew Middleton, Chris Done, Nick Schurch
The Unified Model of AGN predicts the sole difference between Seyfert 1 and Seyfert 2 nuclei is the viewing angle with respect to an obscuring structure around the nucleus. High en…
Suzaku wide-band X-ray Spectroscopy of the Seyfert 2 AGN in NGC 4945
Takeshi Itoh, Chris Done, Kazuo Makishima +13
Suzaku observed a nearby Seyfert 2 galaxy NGC4945, which hosts one of the brightest active galactic nuclei above 20 keV. Combining data from the X-ray CCD camera (XIS) and the Hard…
Modelling the behaviour of accretion flows in X-ray binaries
Chris Done, Marek Gierlinski, Aya Kubota
(abridged) We review how the recent increase in X-ray and radio data from black hole and neutron star binaries can be merged together with theoretical advances to give a coherent p…
An absorption origin for the soft excess in Seyfert 1 AGN
M. J. Middleton, C. Done, M. Gierlinski
(abridged) The soft excess seen in the X-ray spectra of many high mass accretion rate AGN can be well modelled by reflection from a partially ionised accretion disc. However, the d…
The origin of the soft excess in high L/L_Edd AGN
Chris Done
We discuss the origin of the soft X-ray excess seen in AGN. There are clear advantages to models where this arises from atomic processes in partially ionised material rather than w…
Can the soft excess in AGN originate from disc reflection?
Chris Done, Sergei Nayakshin
The soft excess seen in many AGN is most probably due to partially ionized material moving at relativistic speeds close to the black hole. There are currently two potential geometr…
Suzaku discovery of iron absorption lines in outburst spectra of the X-ray transient 4U 1630-472
Aya Kubota, Tadayasu Dotani, Jean Cottam +12
We present the results of six Suzaku observations of the recurrent black hole transient 4U1630-472 during its decline from outburst from February 8 to March 23 in 2006. All observa…
Suzaku Observation of Two Ultraluminous X-Ray Sources in NGC 1313
T. Mizuno, R. Miyawaki, K. Ebisawa +19
Two ultraluminous X-ray sources (ULXs) in the nearby Sb galaxy NGC 1313, named X-1 and X-2, were observed with Suzaku on 2005 September 15. During the observation for a net exposur…
The iron K feature in Narrow Line Seyfert 1's: evidence for a P Cygni profile?
C. Done, M. A. Sobolewska, Marek Gierlinski +1
Narrow Line Seyfert 1 galaxies are generally accreting at high fractions of the Eddington limit. They can show complex X-ray spectra, with a strong `soft excess' below 2 keV and a…
What is the origin of the soft excess in AGN?
Malgorzata A. Sobolewska, Chris Done
We investigate the nature of the soft excess below 1 keV observed in AGN. We use the XMM-Newton data of the low redshift, optically bright quasar, PG 1211+143, and we compare it wi…
Failed disk winds; a physical origin for the soft X-ray excess?
N. J. Schurch, C. Done
The origin of the soft X-ray excess emission observed in many type-1 AGN has been an unresolved problem in X-ray astronomy for over two decades. We develop the model proposed Gierl…
Energy-dependent variability and the origin of the soft X-ray excess in AGN
Marek Gierlinski, Chris Done
The origin of the soft excess seen in many AGN below ~1 keV is still an unsolved problem. It is unlikely to represent a true continuum component as its characteristic 'temperature'…
Analysing the atolls: X-ray spectral transitions of accreting neutron stars
Jeanette Gladstone, Chris Done, Marek Gierlinski
We systematically analyze all the available X-ray spectra of disc accreting neutron stars (atolls and millisecond pulsars) from the RXTE database. We show that while these all have…
Testing Accretion Disk Theory in Black Hole X-ray Binaries
Shane W. Davis, Chris Done, Omer M. Blaes
We present results from spectral modeling of three black hole X-ray binaries: LMC X-3, GRO J1655-40, and XTE J1550-564. Using a sample of disk dominated observations, we fit the da…