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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…
The RS Oph outburst of 2021 monitored in X-rays with NICER
Marina Orio, Keith Gendreau, Morgan Giese +19
The 2021 outburst of the symbiotic recurrent nova RS Oph was monitored with the Neutron Star Interior Composition Explorer Mission (NICER) in the 0.2-12 keV range from day one afte…
Stellar wind variability in Cygnus X-1 from high-resolution excess variance spectroscopy with Chandra
Lucia K. Härer, Michael L. Parker, Ileyk El Mellah +5
Stellar winds of massive stars are known to be driven by line absorption of UV photons, a mechanism which is prone to instabilities, causing the wind to be clumpy. The clumpy struc…
UV/Optical disk reverberation lags despite a faint X-ray corona in the AGN Mrk 335
Erin Kara, Aaron J. Barth, Edward M. Cackett +37
We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an un…
Physics Beyond the Standard Model with Future X-ray Observatories: Projected Constraints on Very-Light Axion-Like Particles with and
Júlia Sisk-Reynés, Christopher S. Reynolds, Michael L. Parker +2
Axion-Like Particles (ALPs) are well-motivated extensions of the Standard Model of Particle Physics and a generic prediction of some string theories. X-ray observations of bright A…
X-ray spectral and timing analysis of the Compton Thick Seyfert 2 galaxy NGC 1068
Indrani Pal, C. S. Stalin, M. L. Parker +2
We present the timing and spectral analysis of the Compton Thick Seyfert 2 active galactic nuclei NGC 1068 observed using {\it NuSTAR} and {\it XMM-Newton}. In this work for the fi…
Comparing Reflection and Absorption Models for the Soft X-ray Variability in the NLS1 AGN UGC 11763
Jiachen Jiang, Luigi C. Gallo, Dirk Grupe +1
We present a spectral analysis of two XMM-Newton observations of the narrow-line Seyfert 1 galaxy UGC 11763. UGC 11763 shows very different soft X-ray spectral shapes in the two ob…
The long-stable hard state of XTE J1752-223 and the disk truncation dilemma
Riley M. T. Connors, Javier A. Garcia, John Tomsick +10
The degree to which the thin accretion disks of black hole X-ray binaries are truncated during hard spectral states remains a contentious open question in black hole astrophysics.…
A New Emulated Monte Carlo Radiative Transfer Disk-Wind Model: X-Ray Accretion Disk-wind Emulator -- XRADE
G. A. Matzeu, M. Lieu, M. T. Costa +14
We present a new X-Ray Accretion Disk-wind Emulator (\textsc{xrade}) based on the 2.5D Monte Carlo radiative transfer code which provides a physically-motivated, self-consistent tr…
AGN X-ray Spectroscopy with Neural Networks
M. L. Parker, M. Lieu, G. A. Matzeu
We explore the possibility of using machine learning to estimate physical parameters directly from AGN X-ray spectra without needing computationally expensive spectral fitting. Spe…
High-density disc reflection spectroscopy of low-mass active galactic nuclei
L. Mallick, A. C. Fabian, J. A. García +13
The standard alpha-disc model predicts an anti-correlation between the density of the inner accretion disc and the black hole mass times square of the accretion rate, as seen in hi…
The X-ray Disk/Wind Degeneracy in AGN
M. L. Parker, G. A. Matzeu, J. H. Matthews +4
Relativistic Fe K emission lines from accretion disks and from disk winds encode key information about black holes, and their accretion and feedback mechanisms. We show that these…
Ionised Emission and Absorption in a Large Sample of Ultraluminous X-ray Sources
P. Kosec, C. Pinto, C. S. Reynolds +6
Most Ultraluminous X-ray sources (ULXs) are thought to be powered by super-Eddington accretion onto stellar-mass compact objects. Accretors in this extreme regime are naturally exp…
The nature of the extreme X-ray variability in the NLS1 1H 0707-495
M. L. Parker, W. N. Alston, L. Härer +11
We examine archival XMM-Newton data on the extremely variable narrow-line Seyfert 1 (NLS1) active galactic nucleus (AGN) 1H 0707-495. We construct fractional excess variance (Fvar)…
MAXI J1820+070 with NuSTAR II. Flaring during the hard to soft state transition with a long soft lag
D. J. K. Buisson, A. C. Fabian, P. Gandhi +6
We continue the analysis of NuSTAR data from the recent discovery outburst of MAXI J1820+070 (optical counterpart ASASSN-18ey), focussing on an observation including unusual flarin…
The first broadband X-ray view of the narrow line Seyfert 1 Ton S180
G. A. Matzeu, E. Nardini, M. L. Parker +15
We present joint \textit{XMM-Newton} and \textit{NuSTAR} observations of the `bare' narrow line Seyfert 1 Ton S180 (), carried out in 2016 and providing the first hard X-r…
The Origin of X-ray Emission in the Gamma-ray emitting Narrow-Line Seyfert 1 1H 0323+342
Sergio A. Mundo, Erin Kara, Edward M. Cackett +7
We present the results of X-ray spectral and timing analyses of the closest gamma-ray emitting narrow-line Seyfert 1 (-NLS1) galaxy, 1H 0323+342. We use observations from a rece…
General Physical Properties of Gamma-ray Emitting Narrow-Line Seyfert 1 Galaxies
Vaidehi S. Paliya, M. L. Parker, J. Jiang +4
We present the results of a detailed multi-wavelength study of a sample of sixteen narrow-line Seyfert 1 (NLSy1) galaxies known in -rays so far. This includes a focused X-ray sp…
NuSTAR observations of Mrk 766: distinguishing reflection from absorption
D. J. K. Buisson, M. L. Parker, E. Kara +14
We present two new NuSTAR observations of the narrow line Seyfert 1 (NLS1) galaxy Mrk 766 and give constraints on the two scenarios previously proposed to explain its spectrum and…
X-ray spectral variability of blazars using principal component analysis
Dennis Gallant, Luigi C. Gallo, Michael L. Parker
Principal Component Analysis (PCA) is applied to a variety of blazars to examine X-ray spectral variability. Data from nine different objects are analysed in two ways: long-term, w…
A high-density relativistic reflection origin for the soft and hard X-ray excess emission from Mrk 1044
Labani Mallick, William N. Alston, Michael L. Parker +7
We present the first results from a detailed spectral-timing analysis of a long (130 ks) XMM-Newton observation and quasi-simultaneous NuSTAR and Swift observations of the hi…
The 1.5 Ms Observing Campaign on IRAS 13224-3809: X-ray Spectral Analysis I
J. Jiang, M. L. Parker, A. C. Fabian +16
We present a detailed spectral analysis of the recent 1.5\,Ms XMM-Newton observing campaign on the narrow line Seyfert 1 galaxy IRAS~132243809, taken simultaneously with 500\,ks…
A Hard Look at the Neutron Stars and Accretion Disks in 4U 1636-53, GX 17+2, and 4U 1705-44 with
R. M. Ludlam, J. M. Miller, M. Bachetti +9
We present observations of neutron star (NS) low-mass X-ray binaries: 4U 1636-53, GX 17+2, and 4U 1705-44. We observed 4U 1636-53 in the hard state, with an Eddingt…
A strongly truncated inner accretion disk in the Rapid Burster
J. van den Eijnden, T. Bagnoli, N. Degenaar +4
The neutron star (NS) low-mass X-ray binary (LMXB) the Rapid Burster (RB; MXB 1730-335) uniquely shows both Type-I and Type-II X-ray bursts. The origin of the latter is ill-underst…