Abstract
4U 1822-371 is a typical edge-on eclipsing low mass X-ray binary and the prototype of accretion disk coronal sources. We report on the results of a spectral analysis over the energy range 0.5-45 keV observed by Suzaku in 2006. We extract spectra from five orbital phases. The spectra can be equally well described by various previously proposed models: an optically thick model described by a partially covered cutoff power law and an optically thin model described by a blackbody plus a cutoff power law. The optically thick model requires a covering fraction of about 55%, while the optically thin model requires a temperature of the central source of about 0.16 keV. The spectrum in the optically thick model also shows the previously detected cyclotron line feature at ∼30 keV with the same Suzaku observation. This feature confirms the presence of a strong magnetic field. The Fe Kα fluorescent line strengths as well as the detected Fe XXVI strengths are similar to previous Chandra and XMM-Newton detections in our phased spectral analysis; however, we also observe strong Fe XXVI during the eclipse, which indicates a slightly larger central corona.
| Original language | English |
|---|---|
| Article number | 057 |
| Journal | Research in Astronomy and Astrophysics |
| Volume | 16 |
| Issue number | 4 |
| DOIs | |
| State | Published - Apr 2016 |
Keywords
- accretion, accretion disks
- binaries: eclipsing
- binaries: spectroscopic
- line: formation
- X-rays: binaries