93 citations · 497 across the 14 of their papers we have counts for
14 papers
X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: an in-depth study with IXPE and NuSTAR
F. Ursini, R. Farinelli, A. Gnarini +101
We report on a comprehensive analysis of simultaneous X-ray polarimetric and spectral data of the bright atoll source GX 9+9 with the Imaging X-ray Polarimetry Explorer (IXPE) and…
The geometry of the hot corona in MCG-05-23-16 constrained by X-ray polarimetry
D. Tagliacozzo, A. Marinucci, F. Ursini +105
We report on the second observation of the radio-quiet active galactic nucleus (AGN) MCG-05-23-16 performed with the Imaging X-ray Polarimetry Explorer (IXPE). The observation star…
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,…
A theoretical study of the time-lags due to Comptonization and the constraints on the X-ray corona in AGN
W. Zhang, I. E. Papadakis, M. Dovčiak +2
We study the Fourier time-lags due to the Comptonization of disc-emitted photons in a spherical, uniform, and stationary X-ray corona, which located on the rotational axis of the b…
Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16
A. Marinucci, F. Muleri, M. Dovčiak +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…
The peculiar spectral evolution of the new X-ray transient MAXI J0637-430
R. C. Ma, R. Soria, L. Tao +15
We studied the transient Galactic black hole candidate MAXI J0637-430 with data from Insight-HXMT, Swift and XMM-Newton. The broad-band X-ray observations from Insight-HXMT help us…
Response of the Fe K_alpha line emission to the X-ray continuum variability in the changing-look active galactic nucleus NGC 1566
W. C. Liang, X. W. Shu, J. X. Wang +5
NGC 1566 is a changing look AGN known to exhibit recurrent X-ray outbursts with each lasting for several years. The most recent X-ray outburst is observed on 2018, with a substanti…
Prospects for differentiating extended coronal geometries in AGNs with the IXPE mission
F. Ursini, G. Matt, S. Bianchi +3
X-ray polarimetry can potentially constrain the unknown geometrical shape of AGN coronae. We present simulations of the X-ray polarization signal expected from AGN coronae, assumin…
A physical model for the broadband energy spectrum of X-ray illuminated accretion discs: fitting the spectral energy distribution of NGC 5548
M. Dovciak, I. E. Papadakis, E. S. Kammoun +1
We develop a new physical model for the broadband spectral energy distribution (SED) of X-ray illuminated accretion discs, that takes into account the mutual interaction of the acc…
Possible ~0.4 hour X-ray quasi-periodicity from an ultrasoft active galactic nucleus
J. R. Song, X. W. Shu, L. M. Sun +6
RX J1301.9+2747 is an ultrasoft active galactic nucleus (AGN) with unusual X-ray variability that is characterized by a long quiescent state and a short-lived flare state. The X-ra…
Towards a complete description of spectra and polarization of black hole accretion disks: albedo profiles and returning radiation
Roberto Taverna, Wenda Zhang, Michal Dovčiak +4
Accretion disks around stellar-mass black holes (BHs) emit radiation peaking in the soft X-rays when the source is in the thermal state. The emerging photons are polarized and, for…
The COSPIX mission: focusing on the energetic and obscured Universe
P. Ferrando, A. Goldwurm, P. Laurent +57
Tracing the formation and evolution of all supermassive black holes, including the obscured ones, understanding how black holes influence their surroundings and how matter behaves…
Strong Field Gravity and X-Ray Observations of 4U1820-30
P. Kaaret, S. Piraino, P. F. Bloser +5
The behavior of quasi-periodic oscillations (QPOs) at frequencies near 1 kHz in the x-ray emission from the neutron star x-ray binary 4U1820-30 has been interpreted as evidence for…
Spectral State Transitions in Aql X-1: Evidence for `Propeller' Effects
S. N. Zhang, W. Yu, W. Zhang
Aql X-1 is a soft X-ray transient source and emits type I X-ray bursts. A spectral state transition was observed with RXTE during its outburst decay in February and March 1997. Its…