Publications (295)
The recent X-ray history of NGC 5506
S. Bianchi, I. Balestra, G. Matt +2
We present a detailed discussion of the spectral and spatial components of NGC 5506, based on XMM-Newton, Chandra and BeppoSAX observations. The overall picture consists of a nucle…
The lively accretion disk in NGC 2992. II. The 2019/2021 X-ray monitoring campaigns
R. Middei, A. Marinucci, V. Braito +8
We report on the short and long term X-ray properties of the bright nearby Seyfert 2 galaxy NGC 2992, which was extensively observed with Swift, XMM-Newton and NuSTAR. Swift target…
LOFT: the Large Observatory For X-ray Timing
M. Feroci, J. W. den Herder, E. Bozzo +245
The LOFT mission concept is one of four candidates selected by ESA for the M3 launch opportunity as Medium Size missions of the Cosmic Vision programme. The launch window is curren…
Thermal disc emission from a rotating black hole: X-ray polarization signatures
M. Dovciak, F. Muleri, R. W. Goosmann +2
Thermal emission from the accretion disc around a black hole can be polarized, due to Thomson scattering in a disc atmosphere. In Newtonian space, the polarization angle must be ei…
Evidence for a relativistic iron line in GRS 1915+105
A. Martocchia, G. Matt, V. Karas +2
We report on the discovery of a relativistic iron Kαfluorescent emission line in the BeppoSAX spectrum of the microquasar GRS 1915+105, taken on April 19, 1998, when the line was…
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…
Symmetric kiloparsec-scale radio knots in NGC 7213: evidence for a confined weak jet and recurrent nuclear activity
G. Bruni, F. Panessa, E. Kammoun +9
Low-luminosity active galactic nuclei (LLAGNs) often host weak radio jets whose propagation is shaped by the surrounding interstellar medium. We investigate the nearby LLAGN NGC721…
Stellar-Mass Black Holes and Their Progenitors
J. M. Miller, P. Uttley, K. Nandra +14
If a black hole has a low spin value, it must double its mass to reach a high spin parameter. Although this is easily accomplished through mergers or accretion in the case of super…
The X-ray properties of the magnetic Cataclysmic Variable UU Col
D. de Martino, G. Matt, K. Mukai +5
XMM-Newton observations aimed at determining for the first time the broad-band X-ray properties of the faint high galactic latitude Intermediate Polar UU Col are presented. We perf…
BeppoSAX observations of soft X-ray Intermediate Polars
D. de Martino, G. Matt, T. Belloni +2
We present broad-band (0.1--90keV) spectral and temporal properties of the three Intermediate Polars, RE0751+144 (PQ Gem), RXJ0558.0+5353 (V405Aur) and RXJ1712.6-2414 (V2400 Oph) b…
The New Hard X-ray Mission
G. Tagliaferri, G. Pareschi, A. Argan +12
The Italian New Hard X-ray Mission (NHXM) has been designed to provide a real breakthrough on a number of hot astrophysical issues that includes: black holes census, the physics of…
Hard X--ray detection of NGC 1068 with BeppoSAX
G. Matt, M. Guainazzi, F. Frontera +14
We report on the first detection above ~10 keV of the archetypal Compton-thick Seyfert 2 galaxy NGC 1068. This detection, obtained with the PDS instrument onboard BeppoSAX in the 2…
X-ray absorption in Compton-thin AGN: the predictions of a model revisited
A. Lamastra, G. C. Perola, G. Matt
The evidence of a decrease with increasing luminosity of the fraction f_{abs} of absorbed and Compton-thin among X-ray (2-10 keV) selected AGN is observationally rather well suppor…
Relativistic spectral features from X-ray illuminated spots and the measure of the black hole mass in AGN
M. Dovciak, S. Bianchi, M. Guainazzi +2
Narrow spectral features in the 5--6 keV range were recently discovered in the X-ray spectra of a few active galactic nuclei. We discuss the possibility that these features are due…
The Broad-band X-ray Spectrum of IC 4329A from a Joint NuSTAR/Suzaku Observation
Laura Brenneman, G. Madejski, F. Fuerst +16
We have obtained a deep, simultaneous observation of the bright, nearby Seyfert galaxy IC 4329A with Suzaku and NuSTAR. Through a detailed spectral analysis, we are able to robustl…
BeppoSAX observations of Narrow-Line Seyfert 1 galaxies: II. Ionized iron features in Arakelian 564
A. Comastri, G. M. Stirpe, C. Vignali +8
The BeppoSAX observations of the bright Narrow-Line Seyfert 1 galaxy Ark 564 are presented along with a high quality optical spectrum taken at the 1.5m telescope at La Silla. The 0…
A 3 dimensional diagnostic diagram for Seyfert 2s: probing X-ray absorption and Compton thickness
L. Bassani, M. Dadina, R. Maiolino +5
We present and discuss a "3-dimensional" diagnostic diagram for Seyfert2 galaxies obtained by means of X-ray and [OIII] data on a large sample of objects (reported in the Appendix)…
The Large Observatory For x-ray Timing
M. Feroci, J. W. den Herder, E. Bozzo +341
The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final down-selection for a launch slot in 2022-2024. Thanks…
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…
The X-ray reflector in NGC 4945: a time and space resolved portrait
A. Marinucci, G. Risaliti, Junfeng Wang +5
We present a time, spectral and imaging analysis of the X-ray reflector in NGC 4945, which reveals its geometrical and physical structure with unprecedented detail. NGC 4945 hosts…
X-ray polarization measurement of the gold standard of radio-quiet active galactic nuclei : NGC 1068
F. Marin, A. Marinucci, M. Laurenti +102
We used the Imaging X-ray Polarimetry Explorer (IXPE) satellite to measure, for the first time, the 2-8 keV polarization of NGC 1068. We pointed IXPE for a net exposure time of 1.1…
The log(N)-log(S) and the Broadband Properties of the Sources in the HELLAS2XMM Survey
A. Baldi, S. Molendi, A. Comastri +3
We present the first results from an XMM-Newton serendipitous medium-deep survey, which covers nearly three square degrees. We show the log(N)-log(S) distributions for the 0.5-2, 2…
Broadband X-ray spectral analysis of the Seyfert 1 galaxy GRS 1734-292
A. Tortosa, A. Marinucci, G. Matt +14
We discuss the broadband X-ray spectrum of GRS 1734-292 obtained from non-simultaneous XMM-Newton and NuSTAR observations, performed in 2009 and 2014, respectively. GRS1734-292 is…
The changing X-ray time lag in MCG-6-30-15
E. Kara, A. C. Fabian, A. Marinucci +6
MCG-6-30-15 is one of the most observed Narrow Line Seyfert 1 galaxies in the X-ray band. In this paper we examine the X-ray time lags in this source using a total of 600 ks in obs…
Measuring the Coronal Properties of IC4329A with NuSTAR
L. W. Brenneman, G. Madejski, F. Fuerst +16
We present an analysis of a ~160 ks NuSTAR observation of the nearby bright Seyfert galaxy IC4329A. The high-quality broadband spectrum enables us to separate the effects of distan…
On the nature of X-ray Bright Optically Normal galaxies
A. Comastri, M. Brusa, P. Ciliegi +10
Multiwavelength observations of the hard X-ray selected sources by Chandra and XMM-Newton surveys have significantly improved our knowledge of the objects responsible of the hard X…
Inner accretion disk disappearance during a radio flare in GRS 1915+105
M. Feroci, G. Matt, G. Pooley +3
Simultaneous X-ray (BeppoSAX, 0.1-300 keV) and radio (Ryle Telescope, 15 GHz) observations of the superluminal galactic source GRS 1915+105 in high flux state were carried out star…
XRISM/Resolve reveals the complex iron structure of NGC 7213: Evidence for radial stratification between inner disk and broad-line region
E. Kammoun, T. Kawamuro, K. Murakami +48
We present the first high-resolution X-ray spectrum of NGC 7213 obtained with XRISM/Resolve, supported by simultaneous XMM-Newton, NuSTAR, and SOAR optical data. The XRISM spectrum…
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…
4U 1344-60: a bright intermediate Seyfert galaxy at z=0.012 with a relativistic Fe Kalpha emission line
E. Piconcelli, M. Sanchez-Portal, M. Guainazzi +6
We present analysis of the optical and X-ray spectra of the low Galactic latitude bright (F(2-10) = 3.6 10^{-11} erg/cm2/s) source 4U 1344-60. On the basis of the optical data we p…
Light bending scenario for accreting black holes in X-ray polarimetry
M. Dovciak, F. Muleri, R. W. Goosmann +2
We discuss a model of an X-ray illuminating source above an accretion disk of a rotating black hole. Within the so called lamp-post scheme we compute the expected (observed) polari…
The XMM/BeppoSAX observation of Mkn 841
P. O. Petrucci, C. Cabanac, G. Henri +9
Mkn 841 has been observed simultaneously by XMM and BeppoSAX in January 2001. Due to operational contingency, the 30ks XMM observation was split into two parts, separated by about…
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…
High resolution X-ray spectroscopy of the Seyfert 1 Mrk841: insights into the warm absorber and warm emitter
A. L. Longinotti, E. Costantini, P. O. Petrucci +6
The Seyfert 1 galaxy Mrk841 was observed five times between 2001 and 2005 by the XMM-Newton X-ray observatory. The source is well known for showing spectral complexity in the varia…
A changing inner radius in the accretion disc of Q0056-363?
G. Matt, D. Porquet, S. Bianchi +4
Q0056-363 is the most powerful X-ray quasar known to exhibit a broad, likely relativistic iron line (Porquet & Reeves 2003). It has been observed twice by XMM-, three and h…
Polarization signatures of strong gravity in black-hole accretion discs
V. Karas, M. Dovciak, G. Matt
We discuss the effects of strong gravity on the polarization properties of a black hole accretion disc. The intrinsic polarization is computed taking into account light scattered o…
The origin of the iron lines in NGC 7213
S. Bianchi, G. Matt, I. Balestra +1
The analysis of a simultaneous XMM-Newton/BeppoSAX plus three previous BeppoSAX observations revealed that NGC 7213 is a rather peculiar Seyfert 1. No significant Compton reflectio…
The BeppoSAX High Energy Large Area Survey -V. The nature of the hard X-ray source populations and its evolution
F. La Franca, F. Fiore, C. Vignali +7
We present optical spectroscopic identifications of hard X-ray (5-10 keV) selected sources belonging to the HELLAS sample obtained with BeppoSAX down to a 5-10 keV flux limit of f_…
NuSTAR and XMM-Newton Observations of the Hard X-Ray Spectrum of Centaurus A
F. Fuerst, C. Mueller, K. K. Madsen +28
We present simultaneous XMM-Newton and NuSTAR observations spanning 3-78 keV of the nearest radio galaxy, Centaurus A (Cen A). The accretion geometry around the central engine in C…
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…
XMM-Newton view of the double-peaked Fe K-alpha complex in E1821+643
E. Jimenez-Bailon, M. Santos-Lleó, E. Piconcelli +3
We present the results of the analysis of the hard band XMM-Newton spectra of the luminous, L(2-10keV)~3.4E+45 erg/s, radio-quiet quasar, E1821+643. Two emission features were obse…
A relativistically smeared spectrum in the neutron star X-ray Binary 4U 1705-44: Looking at the inner accretion disc with X-ray spectroscopy
T. Di Salvo, A. D'Ai', R. Iaria +9
Iron emission lines at 6.4-6.97 keV, identified with fluorescent Kalpha transitions, are among the strongest discrete features in the X-ray band. These are therefore one of the mos…
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…
The properties of the clumpy torus and BLR in the polar-scattered Seyfert 1 galaxy ESO 323-G77 through X-ray absorption variability
G. Miniutti, M. Sanfrutos, T. Beuchert +8
We report results from multi-epoch X-ray observations of the polar-scattered Seyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectral variability from months to years…
The BeppoSAX High Energy Large Area Survey HELLAS, II: Number counts and X-ray spectral properties
F. Fiore, P. Giommi, C. Vignali +7
The BeppoSAX High Energy Large Area Survey (HELLAS) has surveyed about 85 deg^2 of sky in the 5-10 keV band down to a flux of 4-5 10^-14 erg cm-2 s-1. The source surface density of…
Variation in the primary and reprocessed radiation from an orbiting spot around a black hole
M. Dovciak, V. Karas, G. Matt +1
We study light curves and spectra (equivalent widths of the iron line and some other spectral characteristics) which arise by reflection on the surface of an accretion disc, follow…
On the peculiar X-ray properties of the bright nearby radio-quiet quasar PDS456
C. Vignali, A. Comastri, F. Nicastro +3
BeppoSAX and ASCA observations of the nearby (z=0.184), high-luminosity, radio-quiet quasar PDS456 are presented. The X-ray spectrum is characterized by a prominent ionized edge at…
Compton thick AGN in the Suzaku era
A. Comastri, R. Gilli, C. Vignali +3
Suzaku observations of two hard X-ray (> 10 keV) selected nearby Seyfert 2 galaxies are presented. Both sources were clearly detected with the PIN Hard X-ray Detector up to several…
The HELLAS2XMM 1dF survey: on the nature of high X-ray to optical flux ratio sources
F. Fiore, M. Brusa, F. Cocchia +12
We present results from the photometric and spectroscopic identification of 122 X-ray sources discovered by XMM-Newton in the 2-10 keV band (the HELLAS2XMM 1dF sample). One of the…
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…
Flux and spectral variations in the Circinus Galaxy
S. Bianchi, G. Matt, F. Fiore +3
We report on a dramatic flux (50 % increase in the LECS and MECS band) and spectral variation between two BeppoSAX observations of the Circinus Galaxy performed almost three years…
reXcor: A Model of the X-ray Spectrum of Active Galactic Nuclei that Combines Ionized Reflection and a Warm Corona
Xin Xiang, D. R. Ballantyne, S. Bianchi +6
The X-ray spectra of active galactic nuclei (AGNs) often exhibit an excess of emission above the primary power-law at energies <~ keV. Two models for the origin of this `soft e…
The NuSTAR View of Nearby Compton-thick AGN: The Cases of NGC 424, NGC 1320 and IC 2560
M. BalokoviÄ, A. Comastri, F. A. Harrison +25
We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray…
NuSTAR reveals the extreme properties of the super-Eddington accreting SMBH in PG 1247+267
G. Lanzuisi, M. Perna, A. Comastri +26
PG1247+267 is one of the most luminous known quasars at and is a strongly super-Eddington accreting SMBH candidate. We obtained NuSTAR data of this intriguing source in De…
A self-consistent approach to the hard and soft states of 4U 1705-44
A. D'Aì, T. Di Salvo, D. Ballantyne +10
We analyzed two XMM-Newton observations of the bright atoll source 4U 1705-44, which can be considered a prototype of the class of the persistent NS LMXBs showing both hard and sof…
The early stage of a cosmic collision? XMM-Newton unveils two obscured AGN in the galaxy pair ESO509-IG066
M. Guainazzi, E. Piconcelli, E. Jimenez-Bailon +1
We report the XMM-Newton discovery of a X-ray bright AGN pair in the interacting galaxy system ESO509-IG066. Both galaxies host an X-ray luminous (L_X ~10^{43} erg/s) obscured nucl…
Signatures of Resonant Absoprtion in X-ray Spectra of Type 1 AGN
F. Nicastro, F. Fiore, G. Matt
We present photoionization models accounting for both photoelectric and resonant absorption. We demonstrate that resonance absorption lines are detectable even in moderate resoluti…
Relations between phenomenological and physical parameters in the hot coronae of AGNs computed with the MoCA code
R. Middei, S. Bianchi, A. Marinucci +4
The primary X-ray emission in active galactic nuclei (AGNs) is widely believed to be due to Comptonisation of the thermal radiation from the accretion disc in a corona of hot elect…
The High Energy X-ray Probe (HEX-P): Constraining Supermassive Black Hole Growth with Population Spin Measurements
J. M. Piotrowska, J. A. GarcÃa, 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…
Unveiling the nature of the highly obscured AGN in NGC5643 with XMM-Newton
M. Guainazzi, P. Rodriguez-Pascual, A. C. Fabian +2
We present results from an XMM-Newton observation of the nearby Seyfert 2 galaxy NGC5643. The nucleus exhibits a very flat X-ray continuum above 2 keV, together with a prominent K-…
BeppoSAX observations of Narrow-Line Seyfert 1 galaxies:I. Ton S 180
A. Comastri, F. Fiore, M. Guainazzi +10
We report on the first spectrum up to 10 keV of the bright narrow-line Seyfert 1 galaxy Ton S 180, obtained with the imaging instruments onboard BeppoSAX. This is the first observe…
Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16
A. Marinucci, F. Muleri, M. DovÄiak +97
We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) using polarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed with the Imag…
A NuSTAR census of coronal parameters in Seyfert galaxies
A. Tortosa, S. Bianchi, A. Marinucci +2
We discuss the results on the hot corona parameters of Active Galactic Nuclei that have been recently measured with NuSTAR. The values taken from the literature of a sample of nine…
The relativistic shift of narrow spectral features from black-hole accretion discs
T. Pechacek, M. Dovciak, V. Karas +1
Transient spectral features have been discovered in the X-ray spectra of Active Galactic Nuclei, mostly in the 5--7 keV energy range. Several interpretations were proposed for the…
Uncovering the geometry of the hot X-ray corona in the Seyfert galaxy NGC4151 with IXPE
V. E. Gianolli, D. E. Kim, S. Bianchi +106
We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy NGC4151. The source has been observed with the Imaging X-ray Polarimetry Explorer (IXPE) for 700 ks,…
Supermassive Black Hole Spin and Reverberation
A. Zoghbi, D. R. Wilkins, L. Brenneman +7
X-ray reverberation mapping has emerged as a powerful probe of microparsec scales around AGN, and with high sensitivity detectors, its full potential in echo-mapping the otherwise…
The BeppoSAX High Energy Large Area Survey (HELLAS)
F. Fiore, P. Giommi, F. La Franca +9
We have surveyed about 50 deg-2 of sky in the largely unexplored 5-10 keV band using the BeppoSAX MECS instrument, finding 180 sources. After correction for the non uniform sky cov…
Testing Comptonisation models using BeppoSAX observations of Seyfert 1 galaxies
P. O. Petrucci, F. Haardt, L. Maraschi +7
We have used realistic Comptonization models to fit high quality BeppoSAX data of 6 Seyfert galaxies. Our main effort was to adopt a Comptonization model taking into account the an…
The BeppoSAX HELLAS survey: on the nature of faint hard X-ray selected sources
F. Fiore, L. A. Antonelli, P. Ciliegi +8
The BeppoSAX 4.5-10 keV High Energy Large Area Survey has covered about 80 square degrees of sky down to a flux of F(5-10keV)~5E-14 cgs. Optical spectroscopic identification of abo…
BeppoSAX unveils the nuclear component in NGC 6240
P. Vignati, S. Molendi, G. Matt +10
The direct nuclear X-ray emission of the ultraluminous IRAS galaxy NGC 6240 has been observed for the first time by BeppoSAX. It is seen through an absorber with N_H=2*10^{24} cm^{…
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…
High-energy monitoring of NGC 4593 II. Broadband spectral analysis: testing the two-corona model
R. Middei, S. Bianchi, P. -O. Petrucci +9
It is widely believed that the primary X-ray emission of AGN is due to the Comptonisation of optical-UV photons from a hot electron corona, while the origin of the 'soft-excess' is…
X-Ray Polarization from the Atoll 4U 1735-44 Suggests a Low Inclination
M. A. DÃaz Teodori, A. Bobrikova, A. Gnarini +17
X-ray polarimetry is a new tool capable of probing the geometry of accretion onto weakly magnetized neutron stars. Here we present the first X-ray spectropolarimetric results from…
The X-ray emission of the polar BL Hydri
G. Matt, R. Barcaroli, T. Belloni +8
We report on the analysis of the ASCA and BeppoSAX X-ray observations of the polar system BL Hyi. Emission from both poles is apparent in both observations; the emission from the s…
Supermassive Black Hole Winds in X-rays -- SUBWAYS. III. A population study on ultra-fast outflows
V. E. Gianolli, S. Bianchi, P-O Petrucci +44
The detection of blue-shifted absorption lines likely associated with ionized Iron K-shell transitions in the X-ray spectra of many Active Galactic Nuclei (AGN) suggests the presen…
Broad band spectral properties of Seyfert 1 galaxies observed with BeppoSAX
L. Piro, A. De Rosa, M. Dadina +8
We will present some results on the broad--band observations of BeppoSAX of the bright Seyfert galaxies NGC 4151 and NGC 5548.
1RXSJ173021.5-055933: a cataclysmic variable with a fast-spinning magnetic white dwarf
D. de Martino, G. Matt, K. Mukai +8
We present the first X-ray observations with the XMM-Newton and INTEGRAL satellites of the recently discovered cataclysmic variable 1RXSJ173021.5-055933, together with simultaneous…
Transient obscuration event captured in NGC 3227. I. Continuum model for the broadband spectral energy distribution
M. Mehdipour, G. A. Kriss, J. S. Kaastra +21
From Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton…
Radiation spectra of warm and optically thick coronae in AGN
P. -O. Petrucci, D. Gronkiewicz, A. Rozanska +9
A soft X-ray excess above the 2-10 keV power law extrapolation is generally observed in AGN X-ray spectra. Presently there are two competitive models to explain it: blurred ionized…
Accretion geometry of the neutron star low mass X-ray binary Cyg X-2 from X-ray polarization measurements
R. Farinelli, S. Fabiani, J. Poutanen +92
We report spectro-polarimetric results of an observational campaign of the bright neutron star low-mass X-ray binary Cyg X-2 simultaneously observed by IXPE, NICER and INTEGRAL. Co…
Anatomy of the AGN in NGC 5548: II. The Spatial, Temporal and Physical Nature of the Outflow from HST/COS Observations
N. Arav, C. Chamberlain, G. A. Kriss +30
(Abridged) Our deep multiwavelength campaign on NGC 5548 revealed an unusually strong X-ray obscuration. The resulting dramatic decrease in incident ionizing flux allowed us to con…
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…
IXPE Observations of the Blazar Mrk 501 in 2022: A Multiwavelength View
L. Lisalda, E. Gau, H. Krawczynski +157
The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and 2022 July with the Imaging X-ray Polarimetry Explorer (IXPE). In thi…
The complex 0.1-200 keV spectrum of the Seyfert 1 Galaxy NGC4593
M. Guainazzi, G. C. Perola, G. Matt +5
We report on the first observation of the Seyfert 1 galaxy NGC4593 in the 0.1-200 keV band, performed with the BeppoSAX observatory. Its spectral components are for the first time…
Suzaku observations of hard X-ray selected Seyfert 2 galaxies
A. Comastri, K. Iwasawa, R. Gilli +4
We present Suzaku observations of five hard X-ray selected nearby Seyfert 2 galaxies. All the sources were clearly detected with the pin Hard X-ray Detector up to several tens of k…
Suzaku broad-band observations of the Seyfert 1 galaxies Mrk 509 and Mrk 841
M. Cerruti, G. Ponti, C. Boisson +5
We report an analysis and modelling of new Suzaku observations of the Seyfert 1 galaxies Mrk509 and Mrk841, taken between April and November 2006,for Mrk509,and between January and…
Elusive Active Galactic Nuclei
R. Maiolino, A. Comastri, R. Gilli +8
A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optima…
High Energy Large Area Surveys: from BeppoSAX to Chandra and XMM
F. Fiore, A. Comastri, F. La Franca +3
Optical identification of hard X-ray selected BeppoSAX and Chandra sources indicates that a large fraction of the sources are ``intermediate'' AGN, i.e. type 1.8-1.9 AGN, broad-lin…
Estimating the size of X-ray lamppost coronae in active galactic nuclei
F. Ursini, M. DovÄiak, 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…
Detection of blueshifted emission and absorption and a relativistic Iron line in the X-ray spectrum of ESO 323-G077
E. Jimenez-Bailon, Y. Krongold, S. Bianchi +4
We report on the X-ray observation of the Seyfert 1 ESO323-G077 performed with XMM-Newton. The spectra show a complex spectrum with conspicuous absorption and emission features. Th…
NGC3147: a "true" Seyfert 2 without the broad-line region
S. Bianchi, A. Corral, F. Panessa +5
We report on simultaneous optical and X-ray observations of the Seyfert galaxy, NGC3147. The XMM-Newton spectrum shows that the source is unabsorbed in the X-rays ($N_H<5\times10^{…
The X-ray emission of the Intermediate Polar V709 Cas
D. de Martino, G. Matt, K. Mukai +6
We present RXTE and BeppoSAX observations of the Intermediate Polar V709 Cas acquired in 1997 and 1998 respectively. The X-ray emission from 0.1 to 30keV is dominated by the strong…
The HELLAS2XMM survey: II. Multiwavelength observations of P3: an X-ray bright, optically inactive galaxy
A. Comastri, M. Mignoli, P. Ciliegi +11
Recent X-ray surveys have clearly demonstrated that a population of optically dull, X-ray bright galaxies is emerging at 2-10 keV fluxes of the order of 10^{-14} erg cm^{-2} s^{-1}…
The HELLAS2XMM survey. IX. Spectroscopic identification of super-EROs hosting AGNs
R. Maiolino, M. Mignoli, L. Pozzetti +12
We present VLT near-IR spectroscopic observations of three X-ray sources characterized by extremely high X-ray-to-optical ratios (X/O>40), extremely red colors (6.3<R-K<7.4, i.e. E…
Suzaku Observations of the Circinus galaxy
Y. Yang, A. S. Wilson, G. Matt +2
We report Suzaku observations of the active, Compton-thick Circinus galaxy. Observations were obtained with both the X-ray Imaging spectrometer (XIS) and the Hard X-ray Detector (H…
The origin of the soft excess in the luminous quasar HE 1029-1401
B. Vaia, F. Ursini, G. Matt +7
The enigmatic and intriguing phenomenon of the "soft excess" observed in the X-ray spectra of luminous quasars continues to be a subject of considerable interest and debate in the…
The final verdict by XMM-Newton: the X-ray obscured Seyfert galaxy NGC5506 has a broad Fe K-alpha line
M. Guainazzi, S. Bianchi, G. Matt +4
We present the first unambiguous evidence of a broad (Gaussian width ~330 eV) component of the iron K-alpha fluorescent emission line in the X-ray obscured Narrow Line Seyfert 1 Ga…
Variation of the primary and reprocessed radiation in the flare-spot model
M. Dovciak, V. Karas, G. Matt +1
We study light curves and spectra (equivalent widths of the iron line and some other spectral characteristics) which arise by reprocessing on the surface of an accretion disc, foll…
The reprocessing features in the X-ray spectrum of the NELG MCG-5-23-16
I. Balestra, S. Bianchi, G. Matt
We present results from the spectral analysis of the Seyfert 1.9 galaxy MCG-5-23-16, based on ASCA, BeppoSAX, Chandra and XMM-Newton observations. The spectrum of this object shows…
Opening a New Window to Fundamental Physics and Astrophysics: X-ray Polarimetry
E. Costa, R. Bellazzini, P. Soffitta +25
An extensive theoretical literature predicts that X-ray Polarimetry can directly determine relevant physical and geometrical parameters of astrophysical sources, and discriminate b…