Chandra observation of the dipping source XB 1254–690

• Published in: Astronomy and astrophysics (Berlin) Vol. 464; no. 1; pp. 291 - 297
• Main Authors: Iaria, R., Di Salvo, T., Lavagetto, G., D' Aí, A., Robba, N. R.
• Format: Journal Article
• Language: English
• Published: EDP Sciences 01.03.2007
• Subjects: accretion; accretion disks; line: identification; stars: individual: XB 1254–690; stars: neutron; X-rays: binaries; X-rays: stars
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361:20065644

We present the results of a 53 ks long Chandra observation of the dipping source XB 1254–690. During the observation neither bursts or dips were observed. From the zero-order image we estimated the precise X-ray coordinates of the source with a 90% uncertainty of 0.6´´. Since the lightcurve did not show any significant variability, we extracted the spectrum corresponding to the whole observation. We confirmed the presence of the $\ion{Fe}{xxvi}$ Kα absorption lines with a larger accuracy with respect to the previous XMM EPIC pn observation. Assuming that the line width were due to a bulk motion or a turbulence associated to the coronal activity, we estimate that the lines were produced in a photoionized absorber between the coronal radius and the outer edge of the accretion disk.