A detailed X-ray investigation of zeta Pup I: The dataset and some preliminary results
Publication date: 27 January 2012
Authors: Nazé, Y., et al.
Journal: Astronomy & Astrophysics
Aims. One of the closest and brightest massive stars, zeta Puppis, was the first early-type object observed by the current generation of X-ray observatories. These observations provided some surprising results, partly confirming the theoretical predictions while simultaneously unveiling some problematic mismatches with expectations. In this series of papers, we perform a thorough study of zeta Puppis in X-rays, using a decade of XMM-Newton observations.
Methods. The star zeta Puppis was observed 18 times by XMM-Newton, totaling 1 Ms in exposure. This provides the highest quality high-resolution X-ray spectrum of a massive star to date, as well as a perfect dataset for studying X-ray variability in an "archetype" object.
Results. This first paper reports on the data reduction of this unique dataset and provides a few preliminary results. On the one hand, analysis of EPIC low-resolution spectra shows the star to have a remarkably stable X-ray emission from one observation to the next. On the other hand, fitting by a wind model of individual line profiles recorded by RGS confirms the wavelength dependence of the line morphology.Link to publication