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X-ray Polarization of the BL Lac Type Blazar 1ES 0229+200
Steven R. Ehlert, Ioannis Liodakis, Riccardo Middei +110
We present polarization measurements in the band from blazar 1ES 0229+200, the first extreme high synchrotron peaked source to be observed by the Imag…
The Polarized Cosmic Hand: IXPE Observations of PSR B1509-58/MSH 15-52
Roger W. Romani, Josephine Wong, Niccolo Di Lalla +99
We describe IXPE polarization observations of the Pulsar Wind Nebula (PWN) MSH15-52, the `Cosmic Hand'. We find X-ray polarization across the PWN, with B field vectors generally al…
Discovery of X-ray Polarization from the Black Hole Transient Swift J1727.8-1613
Alexandra Veledina, Fabio Muleri, Michal Dovciak +113
We report the first detection of the X-ray polarization of the bright transient Swift J1727.8-1613 with the Imaging X-ray Polarimetry Explorer. The observation was performed at the…
First X-ray polarization measurement confirms the low black-hole spin in LMC X-3
Jiří Svoboda, Michal Dovčiak, James F. Steiner +109
X-ray polarization is a powerful tool to investigate the geometry of accreting material around black holes, allowing independent measurements of the black hole spin and orientation…
A remarkably stable accretion disc in the Seyfert galaxy MCG-5-23-16
Roberto Serafinelli, Andrea Marinucci, Alessandra De Rosa +12
MCG-5-23-16 is a Seyfert 1.9 galaxy at redshift z=0.00849. We analyse here the X-ray spectra obtained with XMM-Newton and NuSTAR data, which are the first contemporaneous observati…
NuSTAR Survey of Obscured Swift/BAT-selected Active Galactic Nuclei: II. Median High-energy Cutoff in Seyfert II Hard X-ray Spectra
M. Baloković, F. A. Harrison, G. Madejski +16
Broadband X-ray spectroscopy of the X-ray emission produced in the coronae of active galactic nuclei (AGN) can provide important insights into the physical conditions very close to…
Estimating the size of X-ray lamppost coronae in active galactic nuclei
F. Ursini, M. Dovčiak, W. Zhang +3
We report estimates of the X-ray coronal size of active galactic nuclei in the lamppost geometry. In this commonly adopted scenario, the corona is assumed for simplicity to be a po…
The soft excess of the NLS1 galaxy Mrk 359 studied with an XMM-Newton-NuSTAR monitoring campaign
R. Middei, P. -O. Petrucci, S. Bianchi +7
XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different emission components of active galactic nuclei (AGNs) and to study the evolution of their different sp…
NuSTAR/XMM-Newton monitoring of the Seyfert 1 galaxy HE 1143-1810. Testing the two-corona scenario
F. Ursini, P. -O. Petrucci, S. Bianchi +11
We test the two-corona accretion scenario for active galactic nuclei in the case of the `bare' Seyfert 1 galaxy HE 1143-1810. We perform a detailed study of the broad-band UV--X-ra…
Chasing obscuration in type-I AGN: discovery of an eclipsing clumpy wind at the outer broad-line region of NGC 3783
M. Mehdipour, J. S. Kaastra, G. A. Kriss +21
In 2016 we carried out a Swift monitoring program to track the X-ray hardness variability of eight type-I AGN over a year. The purpose of this monitoring was to find intense obscur…
A deep X-ray view of the bare AGN Ark 120. II. Evidence for Fe K emission transients
E. Nardini, D. Porquet, J. N. Reeves +3
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 lin…
The nature of the torus in the heavily obscured AGN Markarian 3: an X-ray study
M. Guainazzi, G. Risaliti, H. Awaki +22
In this paper we report the results of an X-ray monitoring campaign on the heavily obscured Seyfert galaxy Markarian 3 carried out between the fall of 2014 and the spring of 2015 w…
Anatomy of the AGN in NGC 5548 VIII. XMM-Newton's EPIC detailed view of an unexpected variable multilayer absorber
M. Cappi, B. De Marco, G. Ponti +21
In 2013 we conducted a large multi-wavelength campaign on the archetypical Seyfert 1 galaxy NGC 5548. Unexpectedly, this usually unobscured source appeared strongly absorbed in the…
Anatomy of the AGN in NGC 5548: VII. Swift study of obscuration and broadband continuum variability
M. Mehdipour, J. S. Kaastra, G. A. Kriss +16
We present our investigation into the long-term variability of the X-ray obscuration and optical-UV-X-ray continuum in the Seyfert 1 galaxy NGC 5548. In 2013 and 2014, the Swift ob…
Suzaku Confirms NGC~3660 is an Unabsorbed Seyfert 2
E. Rivers, M. Brightman, S. Bianchi +3
An enigmatic group of objects, unabsorbed Seyfert 2s may have intrinsically weak broad line regions, obscuration in the line of sight to the BLR but not to the X-ray corona, or so…
NuSTAR catches the unveiling nucleus of NGC 1068
A. Marinucci, S. Bianchi, G. Matt +15
We present a NuSTAR and XMM-Newton monitoring campaign in 2014/2015 of the Compton-thick Seyfert 2 galaxy, NGC 1068. During the August 2014 observation, we detect with NuSTAR a flu…
High-energy monitoring of Seyfert galaxies: the case of NGC 4593
F. Ursini, P. -O. Petrucci, G. Matt +6
We discuss preliminary results from a joint XMM-Newton and NuSTAR monitoring program on the active galactic nucleus NGC 4593, consisting of 5x20 ks observations, spaced by two days…
NuSTAR Observations of the Compton-thick Active Galactic Nucleus and Ultraluminous X-ray Source Candidate in NGC 5643
A. Annuar, P. Gandhi, D. M. Alexander +22
We present two NuSTAR observations of the local Seyfert 2 active galactic nucleus (AGN) and an ultraluminous X-ray source (ULX) candidate in NGC 5643. Together with archival data f…
Black hole feedback in the luminous quasar PDS 456
E. Nardini, J. N. Reeves, J. Gofford +17
The evolution of galaxies is connected to the growth of supermassive black holes in their centers. During the quasar phase, a huge luminosity is released as matter falls onto the b…
Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL
F. Ursini, R. Boissay, P. -O. Petrucci +15
We describe the analysis of the seven broad-band X-ray continuum observations of the archetypal Seyfert 1 galaxy NGC 5548 that were obtained with XMM-Newton or Chandra, simultaneou…
Coronal Properties of the Seyfert 1.9 Galaxy MCG -05-23-016 Determined from Hard X-ray Spectroscopy with NuSTAR
M. Baloković, G. Matt, F. A. Harrison +15
Measurements of the high-energy cut-off in the coronal continuum of active galactic nuclei have long been elusive for all but a small number of the brightest examples. We present a…
The hard X-ray spectrum of NGC 5506 as seen by NuSTAR
G. Matt, M. Balokovic, A. Marinucci +12
NuSTAR observed the bright Compton-thin, narrow line Seyfert 1 galaxy, NGC 5506, for about 56 ks. In agreement with past observations, the spectrum is well fit by a power law with…
The Seyfert 2 galaxy NGC 2110: hard X-ray emission observed by NuSTAR and variability of the iron K line
A. Marinucci, G. Matt, S. Bianchi +16
We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source w…
Revealing the X-ray Variability of AGN with Principal Component Analysis
M. L. Parker, A. C. Fabian, G. Matt +7
We analyse a sample of 26 active galactic nuclei with deep XMM-Newton observations, using principal component analysis (PCA) to find model independent spectra of the different vari…