Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
Abstract
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 when the apparent luminosity significantly exceeds this limit. High apparent luminosity might be produced thanks to geometric beaming of the radiation by an outflow. The outflow half-opening angle, which determines the amplification due to beaming, has never been robustly constrained. Using the Imaging X-ray Polarimetry Explorer, we made the measurement of X-ray polarization in the Galactic X-ray binary Cyg X-3. We find high, over 20%, nearly energy-independent linear polarization, orthogonal to the direction of the radio ejections. These properties unambiguously indicate the presence of a collimating outflow in the X-ray binary Cyg~X-3 and constrain its half-opening angle, <15 degrees. Thus, the source can be used as a laboratory for studying the super-critical accretion regime. This finding underscores the importance of X-ray polarimetry in advancing our understanding of accreting sources.
Keywords
Cite
@article{arxiv.2303.01174,
title = {Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE},
author = {Alexandra Veledina and Fabio Muleri and Juri Poutanen and Jakub Podgorný and Michal Dovčiak and Fiamma Capitanio and Eugene Churazov and Alessandra De Rosa and Alessandro Di Marco and Sofia Forsblom and Philip Kaaret and Henric Krawczynski and Fabio La Monaca and Vladislav Loktev and Alexander A. Lutovinov and Sergey V. Molkov and Alexander A. Mushtukov and Ajay Ratheesh and Nicole Rodriguez Cavero and James F. Steiner and Rashid A. Sunyaev and Sergey S. Tsygankov and Andrzej A. Zdziarski and Stefano Bianchi and Joe S. Bright and Nikolaj Bursov and Enrico Costa and Elise Egron and Javier A. Garcia and David A. Green and Mark Gurwell and Adam Ingram and Jari J. E. Kajava and Ruta Kale and Alex Kraus and Denys Malyshev and Frédéric Marin and Giorgio Matt and Michael McCollough and Ilia A. Mereminskiy and Nikolaj Nizhelsky and Giovanni Piano and Maura Pilia and Carlotta Pittori and Ramprasad Rao and Simona Righini and Paolo Soffitta and Anton Shevchenko and Jiri Svoboda and Francesco Tombesi and Sergei Trushkin and Peter Tsybulev and Francesco Ursini and Martin C. Weisskopf and Kinwah Wu and Iván Agudo and Lucio A. Antonelli and Matteo Bachetti and Luca Baldini and Wayne H. Baumgartner and Ronaldo Bellazzini and Stephen D. Bongiorno and Raffaella Bonino and Alessandro Brez and Niccolò Bucciantini and Simone Castellano and Elisabetta Cavazzuti and Chien-Ting Chen and Stefano Ciprini and Ettore Del Monte and Laura Di Gesu and Niccolò Di Lalla and Immacolata Donnarumma and Victor Doroshenko and Steven R. Ehlert and Teruaki Enoto and Yuri Evangelista and Sergio Fabiani and Riccardo Ferrazzoli and Shuichi Gunji and Kiyoshi Hayashida and Jeremy Heyl and Wataru Iwakiri and Svetlana G. Jorstad and Vladimir Karas and Fabian Kislat and Takao Kitaguchi and Jeffery J. Kolodziejczak and Luca Latronico and Ioannis Liodakis and Simone Maldera and Alberto Manfreda and Andrea Marinucci and Alan P. Marscher and Herman L. Marshall and Francesco Massaro and Ikuyuki Mitsuishi and Tsunefumi Mizuno and Michela Negro and Chi-Yung Ng and Stephen L. O'Dell and Nicola Omodei and Chiara Oppedisano and Alessandro Papitto and George G. Pavlov and Abel L. Peirson and Matteo Perri and Melissa Pesce-Rollins and Pierre-Olivier Petrucci and Andrea Possenti and Simonetta Puccetti and Brian D. Ramsey and John Rankin and Oliver Roberts and Roger W. Romani and Carmelo Sgrò and Patrick Slane and Gloria Spandre and Doug Swartz and Toru Tamagawa and Fabrizio Tavecchio and Roberto Taverna and Yuzuru Tawara and Allyn F. Tennant and Nicholas E. Thomas and Alessio Trois and Roberto Turolla and Jacco Vink and Fei Xie and Silvia Zane},
journal= {arXiv preprint arXiv:2303.01174},
year = {2024}
}
Comments
52 pages, 14 figures, 3 tables. Author version of the article published in Nature Astronomy