297 citations · 703 across the 12 of their papers we have counts for
12 papers
Time-resolved XRISM spectroscopy reveals the evolution and structure of the corona in MCG-6-30-15
D. R. Wilkins, L. W. Brenneman, A. Ogorzalek +7
We present a time-resolved analysis of high-resolution spectra of the AGN MCG-6-30-15 obtained by XRISM alongside broadband spectra from NuSTAR and XMM-Newton during a coordinated…
The Broadband View of the Bare Seyfert PG 1426+015: Relativistic Reflection, the Soft Excess and the Importance of Oxygen
D. J. Walton, A. Madathil-Pottayil, P. Kosec +8
We present results from a deep, coordinated - + observation of the type 1 Seyfert PG 1426+015, a source of particular interest as the most massive reverberati…
Simultaneous NICER and NuSTAR Observations of the Neutron Star Low-mass X-ray Binary Serpens X-1
H. Hall, R. M. Ludlam, J. M. Miller +5
We present the first contemporaneous NICER and NuSTAR analysis of the low-mass X-ray binary Serpens X-1 obtained in June 2023, performing broadband X-ray spectral analysis modeling…
A New Broadband Spectral State in the Ultraluminous X-ray Source Holmberg IX X-1
D. J. Walton, M. Bachetti, P. Kosec +12
We present a series of five new broadband X-ray observations of the ultraluminous X-ray source Holmberg IX X-1, performed by - and in coordination. The first…
The High Energy X-ray Probe (HEX-P): Constraining Supermassive Black Hole Growth with Population Spin Measurements
J. M. Piotrowska, J. A. García, D. J. Walton +24
Constraining the primary growth channel of supermassive black holes (SMBH) remains one the most actively debated questions in the context of cosmological structure formation. Owing…
The High Energy X-ray Probe (HEX-P): Probing the physics of the X-ray corona in active galactic nuclei
E. Kammoun, A. M. Lohfink, M. Masterson +28
The hard X-ray emission in active galactic nuclei (AGN) and black hole X-ray binaries is thought to be produced by a hot cloud of electrons referred to as the corona. This emission…
X-ray Lags in PDS 456 Revealed by Suzaku Observations
Chia-Ying Chiang, E. M. Cackett, A. Zoghbi +5
X-ray reverberation lags from the vicinity of supermassive black holes have been detected in almost 30 AGN. The soft lag, which is the time delay between the hard and soft X-ray li…
Modelling the Extreme X-ray Spectrum of IRAS 13224-3809
Chia-Ying Chiang, D. J. Walton, A. C. Fabian +2
The extreme NLS1 galaxy IRAS 13224-3809 shows significant variability, frequency depended time lags, and strong Fe K line and Fe L features in the long 2011 XMM-Newton observation.…
The NuSTAR spectrum of Mrk 335: Extreme relativistic effects within 2 gravitational radii of the event horizon?
M. L. Parker, D. R. Wilkins, A. C. Fabian +18
We present 3-50 keV NuSTAR observations of the AGN Mrk 335 in a very low flux state. The spectrum is dominated by very strong features at the energies of the iron line at 5-7 keV a…
NuSTAR and XMM-Newton Observations of NGC 1365: Extreme Absorption Variability and a Constant Inner Accretion Disk
D. J. Walton, G. Risaliti, F. A. Harrison +24
We present a spectral analysis of four coordinated NuSTAR+XMM-Newton observations of the Seyfert galaxy NGC 1365. These exhibit an extreme level of spectral variability, which is p…
The soft X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view
G. Matt, A. Marinucci, M. Guainazzi +17
We present simultaneous XMM-Newton and NuSTAR observations of the `bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard X-ray spectral c…
Suzaku observations of 'bare' active galactic nuclei
D. J. Walton, E. Nardini, A. C. Fabian +2
We present a X-ray spectral analysis of a large sample of 25 'bare' active galactic nuclei, sources with little or no complicating intrinsic absorption, observed with Suzaku. Our w…