Astronomy and Astrophysics, volume 538A, 22-22 (2012/2-1)
A detailed X-ray investigation of ζ Puppis. I. The dataset and some preliminary results.
NAZE Y., FLORES C.A. and RAUW G.
Abstract (from CDS):
One of the closest and brightest massive stars, ζ 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 ζPuppis in X-rays, using a decade of XMM-Newton observations. The star ζPuppis 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. 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.