45 citations · 149 across the 19 of their papers we have counts for
24 papers
EXPO: a quantum leap in fast, wide-band X-ray polarimetry for astrophysics
Paolo Soffitta, Sebastien Guillot, Ian Hutchinson +137
The Enhanced X-ray Polarimetry Observatory (EXPO) is a mission concept proposed to ESA as an M8 candidate, with a prospective launch in 2041. Building on the scientific success of…
Accreting stellar-mass black holes
Greg Marcel, Bailey Tetarenko, Adam Ingram +3
Accreting stellar-mass black holes exhibit dramatic variability across the electromagnetic spectrum, including spectral state transitions, outbursts, and jet production, making the…
Discovery of Strong Energy-Dependent X-ray Polarization in the Intermediate State of GS 1354-64
Swati Ravi, Lorenzo Marra, James F. Steiner +20
We report the discovery of significant X-ray polarization from the dynamically confirmed black hole X-ray binary (BHXB) GS 1354-64 during its 2025-2026 outburst, obtained with the…
The First X-Ray Polarimetry of an Eclipsing Low-Mass X-Ray Binary: Serendipitous IXPE Observation of AX J1745.6-2901
Romana Mikušincová, Lorenzo Marra, Hemanth Manikantan +38
We present the first X-ray polarimetric measurement of the neutron star low-mass X-ray binary system AX J1745.6-2901 conducted by the Imaging X-ray Polarimetry Explorer (IXPE) sate…
Super-Eddington Accretion Geometry: a Remarkable Stability of the Hidden Ultraluminous X-Ray Source Cygnus X-3
Romana Mikušincová, Alexandra Veledina, Fabio Muleri +112
We report on the average and orbital phase-resolved polarization of Cyg X-3 in the hard state during the 2023 Imaging X-ray Polarimetry Explorer (IXPE) observational campaign. We f…
Implementing and Verifying a Fourier Domain Approach to Fast Stochastic X-ray Polarimetry Timing
Melissa Ewing, Adam Ingram, John Rankin +1
The launch of the Imaging X-ray Polarimetry Explorer (IXPE), the first space-based polarimeter since 1978, offers a two order of magnitude improvement to the measurement of X-ray p…
Exploring MAXI J1744-294: IXPE insights into a Newly Discovered X-ray Transient
Lorenzo Marra, Romana Mikušincová, Federico M. Vincentelli +33
We present the first IXPE spectro-polarimetric observation of the black hole candidate MAXI J1744294, a transient X-ray source discovered during a bright 2025 outburst in the Ga…
Probing the Strong Gravity Region of Black Holes with eXTP
Qingcui Bu, Cosimo Bambi, Lijun Gou +42
We present the novel capabilities of the enhanced X-ray Timing and Polarimetry (eXTP) mission to study the strong gravity region around stellar-mass black holes in X-ray binary sys…
Variability of X-ray polarization of Cyg X-1
Vadim Kravtsov, Anastasiia Bocharova, Alexandra Veledina +31
We present the results of a three-year X-ray, optical, and radio polarimetric monitoring campaign of the prototypical black hole X-ray binary Cyg X-1, conducted from 2022 to 2024.…
The very high X-ray polarisation of accreting black hole IGRJ17091-3624 in the hard state
Melissa Ewing, Maxime Parra, Guglielmo Mastroserio +26
We report the first detection of the X-ray polarisation of the transient black hole X-ray binary IGRJ17091-3624 taken with the Imaging X-ray polarimetry Explorer (IXPE) in March 20…
Multi-wavelength observations of a jet launch in real time from the post-changing-look Active Galaxy 1ES 1927+654
Sibasish Laha, Eileen T. Meyer, Dev R. Sadaula +34
We present results from a high cadence multi-wavelength observational campaign of the enigmatic changing look AGN 1ES 1927+654 from May 2022- April 2024, coincident with an unprece…
Unobscured radio-quiet Active Galactic Nuclei under the eyes of IXPE
V. E. Gianolli, S. Bianchi, P-O. Petrucci +8
We present the results of the X-ray polarimetric analyses performed on unobscured radio-quiet Active Galactic Nuclei (AGN) with the Imaging X-ray Polarimetry Explorer (IXPE), with…
An IXPE-Led X-ray Spectro-Polarimetric Campaign on the Soft State of Cygnus X-1: X-ray Polarimetric Evidence for Strong Gravitational Lensing
James F. Steiner, Edward Nathan, Kun Hu +134
We present the first X-ray spectropolarimetric results for Cygnus X-1 in its soft state from a campaign of five IXPE observations conducted during 2023 May-June. Companion multiwav…
Recovery of the X-ray polarisation of Swift J1727.81613 after the soft-to-hard spectral transition
J. Podgorný, J. Svoboda, M. Dovčiak +34
We report on the detection of X-ray polarisation in the black-hole X-ray binary Swift J1727.81613 during its dim hard spectral state by the Imaging X-ray Polarimetry Explorer (I…
Dramatic Drop in the X-Ray Polarization of Swift J1727.81613 in the Soft Spectral State
Jiří Svoboda, Michal Dovčiak, James F. Steiner +34
Black-hole X-ray binaries exhibit different spectral and timing properties in different accretion states. The X-ray outburst of a recently discovered and extraordinarily bright sou…
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…
Highly-coherent quasi-periodic oscillations in the 'heartbeat' black hole X-ray binary IGR J17091-3624
Jingyi Wang, Erin Kara, Jeroen Homan +13
IGR J17091-3624 is a black hole X-ray binary (BHXB), often referred to as the 'twin' of GRS 1915+105 because it is the only other known BHXB that can show exotic 'heartbeat'-like v…
The 2022 Outburst of IGR J17091-3624: Connecting the exotic GRS 1915+105 to standard black hole X-ray binaries
Jingyi Wang, Erin Kara, Javier A. García +13
While the standard X-ray variability of black hole X-ray binaries (BHXBs) is stochastic and noisy, there are two known BHXBs that exhibit exotic `heartbeat'-like variability in the…
Detection of X-ray Polarization from the Blazar 1ES 1959+650 with the Imaging X-ray Polarimetry Explorer
Manel Errando, Ioannis Liodakis, Alan P. Marscher +142
Observations of linear polarization in the 2-8 keV energy range with the Imaging X-ray Polarimetry Explorer (IXPE) explore the magnetic field geometry and dynamics of the regions g…
Evidence for a dynamic corona in the short-term time lags of black hole X-ray binary MAXI J1820+070
Niek Bollemeijer, Phil Uttley, Arkadip Basak +19
In X-ray observations of hard state black hole X-ray binaries, rapid variations in accretion disc and coronal power-law emission are correlated and show Fourier-frequency-dependent…
X-ray Polarization of the Eastern Lobe of SS 433
Philip Kaaret, Riccardo Ferrazzoli, Stefano Silvestri +103
How astrophysical systems translate the kinetic energy of bulk motion into the acceleration of particles to very high energies is a pressing question. SS 433 is a microquasar that…
Tracking the X-ray Polarization of the Black Hole Transient Swift J1727.8-1613 during a State Transition
Adam Ingram, Niek Bollemeijer, Alexandra Veledina +120
We report on an observational campaign on the bright black hole X-ray binary Swift J1727.81613 centered around five observations by the Imaging X-ray Polarimetry Explorer (IXPE)…
IXPE observation confirms a high spin in the accreting black hole 4U 1957+115
L. Marra, M. Brigitte, N. Rodriguez Cavero +113
We present the results of the first X-ray polarimetric observation of the low-mass X-ray binary 4U 1957+115, performed with the Imaging X-ray Polarimetry Explorer in May 2023. The…
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…