6533b828fe1ef96bd128859d
RESEARCH PRODUCT
The complex enviroment around Cir X-1
A. D'aíR. IariaT. Di SalvoG. LavagettoN. R. RobbaYe-fei YuanXiang-dong LiDong Laisubject
PhysicsSettore FIS/05 - Astronomia E AstrofisicaSpectrometerAstrophysics::High Energy Astrophysical PhenomenaPhase (waves)X-ray Accretion and accretion disks Neutron stars X-ray binariesFluxAstrophysicsEmission spectrumAbsorption (electromagnetic radiation)Orbital periodSpectral lineLuminositydescription
We present the results of an archival 54 ks long Chandra observation of the peculiar source Cir X–1 during the phase passage 0.223-0.261, based on the phase zero passage at the periastron, of its orbital period. We focus on the study of detected emission and absorption features using the High Energy Transmission Grating Spectrometer on board of the Chandra satellite. A comparative analysis of X-ray spectra, selected at different flux levels of the source, allows us to distinguish between a very hard state, at a low countrate, and a brighter, softer, highly absorbed spectrum during episodes of flaring activity, when the unabsorbed source luminosity is about three times the value in the hard state. The spectrum of the hard state clearly shows emission lines of highly ionized elements, while, during the flaring state, the spectrum also shows strong resonant absorption lines. The most intense ′′ � =
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-01-01 |