Dramatic drop in the X-ray polarization of Swift J1727.8-1613 in the soft spectral state

Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F24%3A00586062" target="_blank" >RIV/67985815:_____/24:00586062 - isvavai.cz</a>
Alternative codes found
RIV/00216208:11320/24:10494061
Result on the web
<a href="https://hdl.handle.net/11104/0353686" target="_blank" >https://hdl.handle.net/11104/0353686</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.3847/2041-8213/ad402e" target="_blank" >10.3847/2041-8213/ad402e</a>

Result language
angličtina
Original language name
Dramatic drop in the X-ray polarization of Swift J1727.8-1613 in the soft spectral state
Original language description
Black hole X-ray binaries exhibit different spectral and timing properties in different accretion states. The X-ray outburst of a recently discovered and extraordinarily bright source, Swift J1727.8-1613, has enabled the first investigation of how the X-ray polarization properties of a source evolve with spectral state. The 2-8 keV polarization degree was previously measured by the Imaging X-ray Polarimetry Explorer (IXPE) to be approximate to 4% in the hard and hard intermediate states. Here we present new IXPE results taken in the soft state, with the X-ray flux dominated by the thermal accretion disk emission. We find that the polarization degree has dropped dramatically to less than or similar to 1%. This result indicates that the measured X-ray polarization is largely sensitive to the accretion state and the polarization fraction is significantly higher in the hard state when the X-ray emission is dominated by upscattered radiation in the X-ray corona. The combined polarization measurements in the soft and hard states disfavor a very high or low inclination of the system.
Czech name
—
Czech description
—

Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10308 - Astronomy (including astrophysics,space science)

Project
<a href="/en/project/GX21-06825X" target="_blank" >GX21-06825X: Accreting Black Holes in the new era of X-ray polarimetry missions</a><br>
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year
2024
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Similar results(10)