| 摘 要： | 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 ke V 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 ke V. The spectrum in the optically thick model also shows the previously detected cyclotron line feature at ~30 ke V 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.
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