Related papers: Decoding Cygnus X-2: The Critical Role of Reflecti…

Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE

The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds the critical value, known as the Eddington limit. Discovery of ultraluminous X-ray sources has shown that accretion can proceed even…

High Energy Astrophysical Phenomena · Physics 2024-08-09 Alexandra Veledina , Fabio Muleri , Juri Poutanen , Jakub Podgorný , Michal Dovčiak , Fiamma Capitanio , Eugene Churazov , Alessandra De Rosa , Alessandro Di Marco , Sofia Forsblom , Philip Kaaret , Henric Krawczynski , Fabio La Monaca , Vladislav Loktev , Alexander A. Lutovinov , Sergey V. Molkov , Alexander A. Mushtukov , Ajay Ratheesh , Nicole Rodriguez Cavero , James F. Steiner , Rashid A. Sunyaev , Sergey S. Tsygankov , Andrzej A. Zdziarski , Stefano Bianchi , Joe S. Bright , Nikolaj Bursov , Enrico Costa , Elise Egron , Javier A. Garcia , David A. Green , Mark Gurwell , Adam Ingram , Jari J. E. Kajava , Ruta Kale , Alex Kraus , Denys Malyshev , Frédéric Marin , Giorgio Matt , Michael McCollough , Ilia A. Mereminskiy , Nikolaj Nizhelsky , Giovanni Piano , Maura Pilia , Carlotta Pittori , Ramprasad Rao , Simona Righini , Paolo Soffitta , Anton Shevchenko , Jiri Svoboda , Francesco Tombesi , Sergei Trushkin , Peter Tsybulev , Francesco Ursini , Martin C. Weisskopf , Kinwah Wu , Iván Agudo , Lucio A. Antonelli , Matteo Bachetti , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolò Bucciantini , Simone Castellano , Elisabetta Cavazzuti , Chien-Ting Chen , Stefano Ciprini , Ettore Del Monte , Laura Di Gesu , Niccolò Di Lalla , Immacolata Donnarumma , Victor Doroshenko , Steven R. Ehlert , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Shuichi Gunji , Kiyoshi Hayashida , Jeremy Heyl , Wataru Iwakiri , Svetlana G. Jorstad , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Jeffery J. Kolodziejczak , Luca Latronico , Ioannis Liodakis , Simone Maldera , Alberto Manfreda , Andrea Marinucci , Alan P. Marscher , Herman L. Marshall , Francesco Massaro , Ikuyuki Mitsuishi , Tsunefumi Mizuno , Michela Negro , Chi-Yung Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel L. Peirson , Matteo Perri , Melissa Pesce-Rollins , Pierre-Olivier Petrucci , Andrea Possenti , Simonetta Puccetti , Brian D. Ramsey , John Rankin , Oliver Roberts , Roger W. Romani , Carmelo Sgrò , Patrick Slane , Gloria Spandre , Doug Swartz , Toru Tamagawa , Fabrizio Tavecchio , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Alessio Trois , Roberto Turolla , Jacco Vink , Fei Xie , Silvia Zane

The X-ray polarisation of the Seyfert 1 galaxy IC 4329A

We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy IC 4329A. The Imaging X-ray Polarimetry Explorer (IXPE) observed the source for ~500 ks, supported by XMM-Newton (~60 ks) and NuSTAR (~80 ks) exposures. We…

High Energy Astrophysical Phenomena · Physics 2023-08-31 A. Ingram , M. Ewing , A. Marinucci , D. Tagliacozzo , D. J. Rosario , A. Veledina , D. E. Kim , F. Marin , S. Bianchi , J. Poutanen , G. Matt , H. L. Marshall , F. Ursini , A. De Rosa , P-O. Petrucci , G. Madejski , T. Barnouin , L. Di Gesu , M. Dovvciak , V. E. Gianolli , H. Krawczynski , V. Loktev , R. Middei , J. Podgorny , S. Puccetti , A. Ratheesh , P. Soffitta , F. Tombesi , S. R. Ehlert , F. Massaro , I. Agudo , L. A. Antonelli , M. Bachetti , L. Baldini , W. H. Baumgartner , R. Bellazzini , S. D. Bongiorno , R. Bonino , A. Brez , N. Bucciantini , F. Capitanio , S. Castellano , E. Cavazzuti , C. -T. Chen , S. Ciprini , E. Costa , E. Del Monte , N. Di Lalla , A. Di Marco , I. Donnarumma , V. Doroshenko , T. Enoto , Y. Evangelista , S. Fabiani , R. Ferrazzoli , J. A. Garcia , S. Gunji , J. Heyl , W. Iwakiri , S. G. Jorstad , P. Kaaret , V. Karas , F. Kislat , T. Kitaguchi , J. J. Kolodziejczak , F. La Monaca , L. Latronico , I. Liodakis , S. Maldera , A. Manfreda , A. P. Marscher , I. Mitsuishi , T. Mizuno , F. Muleri , M. Negro , C. -Y. Ng , S. L. ODell , N. Omodei , C. Oppedisano , A. Papitto , G. G. Pavlov , A. L. Peirson , M. Perri , M. Pesce-Rollins , M. Pilia , A. Possenti , B. D. Ramsey , J. Rankin , O. J. Roberts , R. W. Romani , C. Sgro , P. Slane , G. Spandre , D. A. Swartz , T. Tamagawa , F. Tavecchio , R. Taverna , Y. Tawara , A. F. Tennant , N. E. Thomas , A. Trois , S. S. Tsygankov , R. Turolla , J. Vink , M. C. Weisskopf , K. Wu , F. Xie , S. Zane

INTEGRAL discovery of a high-energy tail in the microquasar Cygnus X-3

The X-ray spectra of X-ray binaries are dominated by emission of either soft or hard X-rays which defines their soft and hard spectral states. Cygnus X-3 is amongst the list of X-ray binaries that show quite complex behavior, with various…

High Energy Astrophysical Phenomena · Physics 2021-01-20 F. Cangemi , J. Rodriguez , V. Grinberg , R. Belmont , P. Laurent , J. Wilms

First INTEGRAL observations of Cygnus X-3

We present the first INTEGRAL results on Cyg X-3 from the PV phase observations of the Cygnus region. The source was clearly detected by the JEM-X, ISGRI and SPI detectors. The INTEGRAL observations were supported by simultaneous pointed…

Astrophysics · Physics 2009-11-10 O. Vilhu , L. Hjalmarsdotter , A. A. Zdziarski , A. Paizis , M. L. McCollough , V. Beckmann , T. J. -L. Courvoisier , K. Ebisawa , P. Kretschmar , P. Goldoni , N. J. Westergaard , P. Hakala , D. Hannikainen

A polarimetrically oriented X-ray stare at the accreting pulsar EXO 2030+375

Accreting X-ray pulsars (XRPs) are presumably ideal targets for polarization measurements, as their high magnetic field strength is expected to polarize the emission up to a polarization degree of ~80%. However, such expectations are being…

High Energy Astrophysical Phenomena · Physics 2023-07-12 Christian Malacaria , Jeremy Heyl , Victor Doroshenko , Sergey S. Tsygankov , Juri Poutanen , Sofia V. Forsblom , Fiamma Capitanio , Alessandro Di Marco , Yujia Du , Lorenzo Ducci , Fabio La Monaca , Alexander A. Lutovinov , Herman L. Marshall , Ilya A. Mereminskiy , Sergey V. Molkov , Mason Ng , Pierre-Olivier Petrucci , Andrea Santangelo , Andrey E. Shtykovsky , Valery F. Suleimanov , Ivan Agudo , Lucio A. Antonelli , Matteo Bachetti , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolo Bucciantini , Simone Castellano , Elisabetta Cavazzuti , Chien-Ting Chen , Stefano Ciprini , Enrico Costa , Alessandra De Rosa , Ettore Del Monte , Laura Di Gesu , Niccolo Di Lalla , Immacolata Donnarumma , Michal Dovciak , Steven R. Ehlert , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Wataru Iwakiri , Svetlana G. Jorstad , Philip Kaaret , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Jeffery J. Kolodziejczak1 , Henric Krawczynski , Luca Latronico , Ioannis Liodakis , Simone Maldera , Alberto Manfreda , Frederic Marin , Andrea Marinucci , Alan P. Marscher , Francesco Massaro , Giorgio Matt , Ikuyuki Mitsuishi , Tsunefumi Mizuno , Fabio Muleri , Michela Negro , Chi-Yung Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel L. Peirson , Matteo Perri , Melissa Pesce-Rollins , Maura Pilia , Andrea Possenti , Simonetta Puccetti , Brian D. Ramsey , John Rankin , Ajay Ratheesh , Oliver J. Roberts , Roger W. Romani , Carmelo Sgro , Patrick Slane , Paolo Soffitta , Gloria Spandre , Douglas A. Swartz , Toru Tamagawa , Fabrizio Tavecchio , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Francesco Tombesi , Alessio Trois , Roberto Turolla , Jacco Vink , Martin C. Weisskopf , Kinwah Wu , Fei Xie , Silvia Zane

Determination of X-ray pulsar geometry with IXPE polarimetry

Using observations of X-ray pulsar Her X-1 by the Imaging X-ray Polarimetry Explorer, we report on a highly significant ($>17\sigma$) detection of the polarization signal from an accreting neutron star. The observed degree of the linear…

High Energy Astrophysical Phenomena · Physics 2023-01-16 Victor Doroshenko , Juri Poutanen , Sergey S. Tsygankov , Valery F. Suleimanov , Matteo Bachetti , Ilaria Caiazzo , Enrico Costa , Alessandro Di Marco , Jeremy Heyl , Fabio La Monaca , Fabio Muleri , Alexander A. Mushtukov , George G. Pavlov , Brian D. Ramsey , John Rankin , Andrea Santangelo , Paolo Soffitta , Rüdiger Staubert , Martin C. Weisskopf , Silvia Zane , Iván Agudo , Lucio A. Antonelli , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolò Bucciantini , Fiamma Capitanio , Simone Castellano , Elisabetta Cavazzuti , Stefano Ciprini , Alessandra De Rosa , Ettore Del Monte , Laura Di Gesu , Niccolò Di Lalla , Immacolata Donnarumma , Michal Dovciak , Steven R. Ehlert , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Wataru Iwakiri , Svetlana G. Jorstad , Vladimir Karas , Takao Kitaguchi , Jeffery J. Kolodziejczak , Henric Krawczynski , Luca Latronico , Ioannis Liodakis , Simone Maldera , Alberto Manfreda , Frédéric Marin , Andrea Marinucci , Alan P. Marscher , Herman L. Marshall , Giorgio Matt , Ikuyuki Mitsuishi , Tsunefumi Mizuno , C. -Y. Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , Abel L. Peirson , Matteo Perri , Melissa Pesce-Rollins , Maura Pilia , Andrea Possenti , Simonetta Puccetti , Ajay Ratheesh , Roger W. Romani , Carmelo Sgrò , Patrick Slane , Gloria Spandre , Rashid A. Sunyaev , Toru Tamagawa , Fabrizio Tavecchio , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicolas E. Thomas , Francesco Tombesi , Alessio Trois , Roberto Turolla , Jacco Vink , Kinwah Wu , Fei Xie

The innermost jet in the hidden ultra-luminous X-ray source Cygnus X-3

Cygnus X-3 is a high-mass X-ray binary with a compact object accreting matter from a Wolf-Rayet donor star. Recently, it has been revealed by the Imaging X-ray Polarimetry Explorer (IXPE) as a hidden Galactic ultra-luminous X-ray (ULX)…

High Energy Astrophysical Phenomena · Physics 2023-08-09 Jun Yang , Federico García , Santiago del Palacio , Ralph Spencer , Zsolt Paragi , Noel Castro Segura , Biping Gong , Hongmin Cao , Wen Chen

Polarized X-rays Correlated with Short--Timescale Variability of Cygnus X-1

We systematically investigate the variability of polarized X-rays on a timescale of a few seconds in the low/hard state of the black hole binary Cygnus X-1. The correlation between polarization degrees and angles with X-Ray intensity was…

High Energy Astrophysical Phenomena · Physics 2024-08-08 Kaito Ninoyu , Yuusuke Uchida , Shinya Yamada , Takayoshi Kohmura , Taichi Igarashi , Ryota Hayakawa , Tenyo Kawamura

AstroSat/LAXPC observation of Cygnus X-1 in the hard state

We report the first analysis of data from AstroSat/LAXPC observations of Cygnus X-1 in January 2016. LAXPC spectra reveals that the source was in the canonical hard state, represented by a prominent thermal Comptonization component having a…

High Energy Astrophysical Phenomena · Physics 2017-02-08 Ranjeev Misra , J S Yadav , Jai Verdhan Chauhan , P C Agrawal , H M Antia , Mayukh Pahari , V R Chitnis , Dhiraj Dedhia , Tilak Katoch , P. Madhwani , R K Manchanda , B Paul , Parag Shah

The NuSTAR View of Nearby Compton-thick AGN: The Cases of NGC 424, NGC 1320 and IC 2560

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 spectra allow detailed modeling of the Compton reflection…

High Energy Astrophysical Phenomena · Physics 2014-12-19 M. Baloković , A. Comastri , F. A. Harrison , D. M. Alexander , D. R. Ballantyne , F. E. Bauer , S. E. Boggs , W. N. Brandt , M. Brightman , F. E. Christensen , W. W. Craig , A. Del Moro , P. Gandhi , C. J. Hailey , M. Koss , G. B. Lansbury , B. Luo , G. M. Madejski , A. Marinucci , G. Matt , C. B. Markwardt , S. Puccetti , C. S. Reynolds , G. Risaliti , E. Rivers , D. Stern , D. J. Walton , W. W. Zhang

X-ray polarization from parsec-scale components of active galactic nuclei: observational prospects

We present a broad analysis of X-ray polarimetric observational prospects for radio-quiet active galactic nuclei (AGN), focusing on the role of parsec-scale components. We provide a revision of self-consistent type-1 and type-2 generic AGN…

High Energy Astrophysical Phenomena · Physics 2023-10-25 J. Podgorný , F. Marin , M. Dovčiak

X-ray spectro-polarimetric characterization of GX 340+0 in the horizontal branch: a highly inclined source?

We report the first detection of X-ray polarization in the horizontal branch for GX 340+0 as obtained by Imaging X-ray Polarimetry Explorer (IXPE). A polarization degree of 4.3%$\pm$0.3% is obtained. This value is in agreement with the…

High Energy Astrophysical Phenomena · Physics 2024-11-21 Fabio La Monaca , Alessandro Di Marco , Renee M. Ludlam , Anna Bobrikova , Juri Poutanen , Songwei Li , Fei Xie

IXPE Observation of the Low-Synchrotron Peaked Blazar S4 0954+65 During An Optical-X-ray Flare

The X-ray polarization observations made possible with the Imaging X-ray Polarimetry Explorer (IXPE) offer new ways of probing high-energy emission processes in astrophysical jets from blazars. Here we report on the first X-ray polarization…

High Energy Astrophysical Phenomena · Physics 2025-03-12 Pouya M. Kouch , Ioannis Liodakis , Francesco Fenu , Haocheng Zhang , Stella Boula , Riccardo Middei , Laura Di Gesu , Georgios F. Paraschos , Iván Agudo , Svetlana G. Jorstad , Elina Lindfors , Alan P. Marscher , Henric Krawczynski , Michela Negro , Kun Hu , Dawoon E. Kim , Elisabetta Cavazzuti , Manel Errando , Dmitry Blinov , Anastasia Gourni , Sebastian Kiehlmann , Angelos Kourtidis , Nikos Mandarakas , Nikolaos Triantafyllou , Anna Vervelaki , George A. Borman , Evgenia N. Kopatskaya , Elena G. Larionova , Daria A. Morozova , Sergey S. Savchenko , Andrey A. Vasilyev , Ivan S. Troitskiy , Tatiana S. Grishina , Alexey V. Zhovtan , Francisco José Aceituno , Giacomo Bonnoli , Víctor Casanova , Juan Escudero , Beatriz Agís-González , César Husillos , Jorge Otero-Santos , Vilppu Piirola , Alfredo Sota , Ioannis Myserlis , Mark Gurwell , Garrett K. Keating , Ramprasad Rao , Emmanouil Angelakis , Alexander Kraus , Lucio Angelo Antonelli , Matteo Bachetti , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolò Bucciantini , Fiamma Capitanio , Simone Castellano , Chien-Ting Chen , Stefano Ciprini , Enrico Costa , Alessandra De Rosa , Ettore Del Monte , Niccolò Di Lalla , Alessandro Di Marco , Immacolata Donnarumma , Victor Doroshenko , Michal Dovčiak , Steven R. Ehlert , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Jeremy Heyl , Wataru Iwakiri , Philip Kaaret , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Jeffery J. Kolodziejczak , Fabio La Monaca , Luca Latronico , Simone Maldera , Alberto Manfreda , Frédéric Marin , Andrea Marinucci , Herman L. Marshall , Francesco Massaro , Giorgio Matt , Ikuyuki Mitsuishi , Tsunefumi Mizuno , Fabio Muleri , Chi-Yung Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel Lawrence Peirson , Matteo Perri , Melissa Pesce-Rollins , Pierre-Olivier Petrucci , Maura Pilia , Andrea Possenti , Juri Poutanen , Simonetta Puccetti , Brian D. Ramsey , John Rankin , Ajay Ratheesh , Oliver J. Roberts , Carmelo Sgrò , Patrick Slane , Paolo Soffitta , Gloria Spandre , Douglas A. Swartz , Toru Tamagawa , Fabrizio Tavecchio , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Francesco Tombesi , Alessio Trois , Sergey S. Tsygankov , Roberto Turolla , Roger W. Romani , Jacco Vink , Martin C. Weisskopf , Kinwah Wu , Fei Xie , Silvia Zane

Discovery of Red-Skewed K_alpha iron line in Cyg X-2 with Suzaku

We report on the Suzaku observation of neutron star low-mass X-ray binary Cygnus X-2 which reveals a presence of the iron K_alpha emission line. The line profile shows a significant red wing. This discovery increases the number of neutron…

High Energy Astrophysical Phenomena · Physics 2009-07-22 Nikolai Shaposhnikov , Lev Titarchuk , Philippe Laurent

Lamp-post with an outflow and the hard state of Cyg X-1

Relativistic reflection observed in the hard states of accreting black holes often shows a weak amplitude relative to the main Comptonization component, which may result from either a disc truncation or a non-isotropy of the X-ray source,…

High Energy Astrophysical Phenomena · Physics 2022-12-14 Lukasz Klepczarek , Andrzej Niedzwiecki , Michal Szanecki

Vanishing hardness-flux correlation in Cygnus X-1: signs of the disc moving out

Aims. We investigate observations of the X-ray binary Cygnus X-1 with unusually high hardness and low flux. In particular, we study the characteristic frequencies seen in the PDS and the hardness-flux correlation within and between these…

Astrophysics · Physics 2009-02-25 M. Axelsson , L. Hjalmarsdotter , L. Borgonovo , S. Larsson

Effects of the stellar wind on X-ray spectra of Cygnus X-3

We study X-ray spectra of Cyg X-3 from BeppoSAX, taking into account absorption and emission in the strong stellar wind of its companion. We find the intrinsic X-ray spectra are well modelled by disc blackbody emission, its upscattering by…

Astrophysics · Physics 2009-11-13 A. Szostek , A. A. Zdziarski

Detection of gamma rays of likely jet origin in Cygnus X-1

Aims: Probe the high-energy ($>$60 MeV) emission from the black hole X-ray binary system, Cygnus X-1, and investigate its origin. Methods: We analysed 7.5 yr of data by Fermi/LAT with the latest PASS8 software version. Results: We report…

High Energy Astrophysical Phenomena · Physics 2016-11-30 Roberta Zanin , Alba Fernández-Barral , Emma de Oña-Wilhelmi , Felix Aharonian , Oscar Blanch , Valentí Bosch-Ramon , Daniel Galindo

Exploring polarization and geometry in the X-ray pulsar 4U 1538-52

The Imaging X-ray Polarimetry Explorer (IXPE) observations of accreting X-ray pulsars (XRPs) continue to provide novel insights into the physics and geometry of these sources. We present the first X-ray polarimetric study of the persistent…

High Energy Astrophysical Phenomena · Physics 2025-05-28 Vladislav Loktev , Sofia V. Forsblom , Sergey S. Tsygankov , Juri Poutanen , Alexander A. Mushtukov , Alessandro Di Marco , Jeremy Heyl , Ruth M. E. Kelly , Fabio La Monaca , Mason Ng , Swati Ravi , Alexander Salganik , Andrea Santangelo , Valery F. Suleimanov , Silvia Zane

Circumnuclear Multi-phase Gas in the Circinus Galaxy. V. The Origin of the X-Ray Polarization in the Circinus Galaxy

The Imaging X-ray Polarimetry Explorer (IXPE) detected X-ray polarization in the nearest Seyfert 2 galaxy, the Circinus galaxy, for the first time. To reproduce the IXPE results, we computed the degree of polarization based on two types of…

High Energy Astrophysical Phenomena · Physics 2023-10-31 Atsushi Tanimoto , Keiichi Wada , Yuki Kudoh , Hirokazu Odaka , Ryosuke Uematsu , Shoji Ogawa