Discovery of X-Ray Polarization from the Black Hole Transient Swift J1727.8-1613

0582175 - ASÚ 2024 RIV US eng J - Článek v odborném periodiku
Veledina, A. - Muleri, F. - Dovčiak, Michal - Svoboda, Jiří - Podgorný, Jakub - Karas, Vladimír … celkem 116 autorů
Discovery of X-Ray Polarization from the Black Hole Transient Swift J1727.8-1613.
Astrophysical Journal Letters. Roč. 958, č. 1 (2023), č. článku L16. ISSN 2041-8205. E-ISSN 2041-8213
Grant CEP: GA ČR(CZ) GX21-06825X
Institucionální podpora: RVO:67985815
Klíčová slova: accretion * X-ray astronomy * low-mass x-ray binary stars
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 7.9, rok: 2022
Způsob publikování: Open access

We report the first detection of the X-ray polarization of the bright transient Swift J1727.8-1613 with the Imaging X-ray Polarimetry Explorer. The observation was performed at the beginning of the 2023 discovery outburst, when the source resided in the bright hard state. We find a time- and energy-averaged polarization degree of 4.1% ± 0.2% and a polarization angle of 2.°2 ± 1.°3 (errors at 68% confidence level, this translates to ~20σ significance of the polarization detection). This finding suggests that the hot corona emitting the bulk of the detected X-rays is elongated, rather than spherical. The X-ray polarization angle is consistent with that found in submillimeter wavelengths. Since the submillimeter polarization was found to be aligned with the jet direction in other X-ray binaries, this indicates that the corona is elongated orthogonal to the jet.
Trvalý link: https://hdl.handle.net/11104/0350254