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arXiv · 2308.01238

IXPE and XMM-Newton observations of the Soft Gamma Repeater SGR 1806-20

Roberto Turolla·Roberto Taverna·Gian Luca Israel·Fabio Muleri·Silvia Zane·Matteo Bachetti·Jeremy Heyl·Alessandro Di Marco·Ephraim Gau·Henric Krawczynski·Mason Ng·Andrea Possenti·Juri Poutanen·Luca Baldini·Giorgio Matt·Michela Negro·Ivan Agudo·Lucio Angelo Antonelli·Wayne H. Baumgartner·Ronaldo Bellazzini·Stefano Bianchi·Stephen D. Bongiorno·Raffaella Bonino·Alessandro Brez·Niccolo' Bucciantini·Fiamma Capitanio·Simone Castellano·Elisabetta Cavazzuti·Chien-Ting J. Chen·Stefano Ciprini·Enrico Costa·Alessandra De Rosa·Ettore Del Monte·Laura Di Gesu·Niccolo' Di Lalla·Immacolata Donnarumma·Victor Doroshenko·Michal Doviak·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·Jeffrey Kolodziejczak·Fabio La Monaca·Luca Latronico·Ioannis Liodakis·Simone Maldera·Alberto Manfreda·Frederic Marin·Andrea Marinucci·Alan P. Marscher·Herman L. Marshall·Francesco Massaro·Ikuyuki Mitsuishi·Tsunefumi Mizuno·Stephen 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·Maura Pilia·Simonetta Puccetti·Brian 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·Yuzuru Tawara·Allyn F. Tennant·N. Thomas·Francesco Tombesi·Alessio Trois·Sergey S. Tsygankov·Jacco Vink·Martin C. Weisskopf·Kinwah Wu·Fei Xie

Abstract

Recent observations with the Imaging X-ray Polarimetry Explorer (IXPE) of two anomalous X-ray pulsars provided evidence that X-ray emission from magnetar sources is strongly polarized. Here we report on the joint IXPE and XMM-Newton observations of the soft {\gamma}-repeater SGR 1806-20. The spectral and timing properties of SGR 1806-20 derived from XMM-Newton data are in broad agreement with previous measurements; however, we found the source at an all-time-low persistent flux level. No significant polarization was measured apart from the 4-5 keV energy range, where a probable detection with PD=31.6\pm 10.5% and PA=-17.6\pm 15 deg was obtained. The resulting polarization signal, together with the upper limits we derive at lower and higher energies 2-4 and 5-8 keV, respectively) is compatible with a picture in which thermal radiation from the condensed star surface is reprocessed by resonant Compton scattering in the magnetosphere, similar to what proposed for the bright magnetar 4U 0142+61.

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Roberto Turolla, Roberto Taverna, Gian Luca Israel, Fabio Muleri, Silvia Zane, Matteo Bachetti, Jeremy Heyl, Alessandro Di Marco, Ephraim Gau, Henric Krawczynski, Mason Ng, Andrea Possenti, Juri Poutanen, Luca Baldini, Giorgio Matt, Michela Negro, Ivan Agudo, Lucio Angelo Antonelli, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccolo' Bucciantini, Fiamma Capitanio, Simone Castellano, Elisabetta Cavazzuti, Chien-Ting J. Chen, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Laura Di Gesu, Niccolo' Di Lalla, Immacolata Donnarumma, Victor Doroshenko, Michal Doviak, 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, Jeffrey Kolodziejczak, Fabio La Monaca, Luca Latronico, Ioannis Liodakis, Simone Maldera, Alberto Manfreda, Frederic Marin, Andrea Marinucci, Alan P. Marscher, Herman L. Marshall, Francesco Massaro, Ikuyuki Mitsuishi, Tsunefumi Mizuno, Stephen 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, Maura Pilia, Simonetta Puccetti, Brian 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, Yuzuru Tawara, Allyn F. Tennant, N. Thomas, Francesco Tombesi, Alessio Trois, Sergey S. Tsygankov, Jacco Vink, Martin C. Weisskopf, Kinwah Wu, Fei Xie. 2023-08-02. IXPE and XMM-Newton observations of the Soft Gamma Repeater SGR 1806-20. https://arxiv.org/abs/2308.01238

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