Chandra observation of the dipping source XB 1254–690
Dipartimento di Scienze Fisiche ed Astronomiche, Università di Palermo, via Archirafi 36, 90123 Palermo, Italy e-mail: email@example.com
Accepted: 6 December 2006
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 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.
Key words: accretion, accretion disks / stars: individual: XB 1254–690 / stars: neutron / X-rays: stars / X-rays: binaries / line: identification
© ESO, 2007