Recovery of the X-ray polarisation of Swift J1727.8-1613 after the soft-to-hard spectral transition

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F24%3A00587336" target="_blank" >RIV/67985815:_____/24:00587336 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/24:10494188

Výsledek na webu

<a href="https://hdl.handle.net/11104/0354775" target="_blank" >https://hdl.handle.net/11104/0354775</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202450566" target="_blank" >10.1051/0004-6361/202450566</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Recovery of the X-ray polarisation of Swift J1727.8-1613 after the soft-to-hard spectral transition

Popis výsledku v původním jazyce

We report on the detection of X-ray polarisation in the black-hole X-ray binary Swift J1727.8-1613 during its dim hard spectral state by the Imaging X-ray Polarimetry Explorer (IXPE). This is the first detection of X-ray polarisation at the transition from the soft to the hard state in an X-ray binary. We find an averaged 2-8 keV polarisation degree of (3.3 +/- 0.4)% and a corresponding polarisation angle of 3 degrees +/- 4 degrees, which matches the polarisation detected during the rising stage of the outburst, in September-October 2023, within 1 sigma uncertainty. The observational campaign complements previous studies of this source and enables comparison of the X-ray polarisation properties of a single transient across the X-ray hardness-intensity diagram. The complete recovery of the X-ray polarisation properties, including the energy dependence, came after a dramatic drop in the X-ray polarisation during the soft state. The new IXPE observations in the dim hard state at the reverse transition indicate that the accretion properties, including the geometry of the corona, appear to be strikingly similar to the bright hard state during the outburst rise despite the X-ray luminosities differing by two orders of magnitude.

Název v anglickém jazyce

Recovery of the X-ray polarisation of Swift J1727.8-1613 after the soft-to-hard spectral transition

Popis výsledku anglicky

We report on the detection of X-ray polarisation in the black-hole X-ray binary Swift J1727.8-1613 during its dim hard spectral state by the Imaging X-ray Polarimetry Explorer (IXPE). This is the first detection of X-ray polarisation at the transition from the soft to the hard state in an X-ray binary. We find an averaged 2-8 keV polarisation degree of (3.3 +/- 0.4)% and a corresponding polarisation angle of 3 degrees +/- 4 degrees, which matches the polarisation detected during the rising stage of the outburst, in September-October 2023, within 1 sigma uncertainty. The observational campaign complements previous studies of this source and enables comparison of the X-ray polarisation properties of a single transient across the X-ray hardness-intensity diagram. The complete recovery of the X-ray polarisation properties, including the energy dependence, came after a dramatic drop in the X-ray polarisation during the soft state. The new IXPE observations in the dim hard state at the reverse transition indicate that the accretion properties, including the geometry of the corona, appear to be strikingly similar to the bright hard state during the outburst rise despite the X-ray luminosities differing by two orders of magnitude.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GX21-06825X" target="_blank" >GX21-06825X: Akreující černé díry v nové éře polarizačních rentgenových misí</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Svazek periodika

686

Číslo periodika v rámci svazku

June

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

8

Strana od-do

L12

Kód UT WoS článku

001248216300024

EID výsledku v databázi Scopus

2-s2.0-85196160475