The X-Ray Polarimetry View of the Accreting Pulsar Cen X-3

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F22%3A00571388" target="_blank" >RIV/67985815:_____/22:00571388 - isvavai.cz</a>

Výsledek na webu

<a href="https://hdl.handle.net/11104/0342626" target="_blank" >https://hdl.handle.net/11104/0342626</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/2041-8213/aca486" target="_blank" >10.3847/2041-8213/aca486</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The X-Ray Polarimetry View of the Accreting Pulsar Cen X-3

Popis výsledku v původním jazyce

The first X-ray pulsar, Cen X-3, was discovered 50 yr ago. Radiation from such objects is expected to be highly polarized due to birefringence of plasma and vacuum associated with propagation of photons in the presence of the strong magnetic field. Here we present results of the observations of Cen X-3 performed with the Imaging X-ray Polarimetry Explorer. The source exhibited significant flux variability and was observed in two states different by a factor of similar to 20 in flux. In the low-luminosity state, no significant polarization was found in either pulse phase-averaged (with a 3 sigma upper limit of 12%) or phase-resolved (the 3 sigma upper limits are 20%-30%) data. In the bright state, the polarization degree of 5.8% +/- 0.3% and polarization angle of 49.degrees 6 +/- 1.degrees 5 with a significance of about 20 sigma were measured from the spectropolarimetric analysis of the phase-averaged data. The phase-resolved analysis showed a significant anticorrelation between the flux and the polarization degree, as well as strong variations of the polarization angle. The fit with the rotating vector model indicates a position angle of the pulsar spin axis of about 49 degrees and a magnetic obliquity of 17 degrees. The detected relatively low polarization can be explained if the upper layers of the neutron star surface are overheated by the accreted matter and the conversion of the polarization modes occurs within the transition region between the upper hot layer and a cooler underlying atmosphere. A fraction of polarization signal can also be produced by reflection of radiation from the neutron star surface and the accretion curtain.

Název v anglickém jazyce

The X-Ray Polarimetry View of the Accreting Pulsar Cen X-3

Popis výsledku anglicky

The first X-ray pulsar, Cen X-3, was discovered 50 yr ago. Radiation from such objects is expected to be highly polarized due to birefringence of plasma and vacuum associated with propagation of photons in the presence of the strong magnetic field. Here we present results of the observations of Cen X-3 performed with the Imaging X-ray Polarimetry Explorer. The source exhibited significant flux variability and was observed in two states different by a factor of similar to 20 in flux. In the low-luminosity state, no significant polarization was found in either pulse phase-averaged (with a 3 sigma upper limit of 12%) or phase-resolved (the 3 sigma upper limits are 20%-30%) data. In the bright state, the polarization degree of 5.8% +/- 0.3% and polarization angle of 49.degrees 6 +/- 1.degrees 5 with a significance of about 20 sigma were measured from the spectropolarimetric analysis of the phase-averaged data. The phase-resolved analysis showed a significant anticorrelation between the flux and the polarization degree, as well as strong variations of the polarization angle. The fit with the rotating vector model indicates a position angle of the pulsar spin axis of about 49 degrees and a magnetic obliquity of 17 degrees. The detected relatively low polarization can be explained if the upper layers of the neutron star surface are overheated by the accreted matter and the conversion of the polarization modes occurs within the transition region between the upper hot layer and a cooler underlying atmosphere. A fraction of polarization signal can also be produced by reflection of radiation from the neutron star surface and the accretion curtain.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

Astrophysical Journal Letters

ISSN

2041-8205

e-ISSN

2041-8213

Svazek periodika

941

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

L14

Kód UT WoS článku

000920360500001

EID výsledku v databázi Scopus

2-s2.0-85144807046