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Description
Using XMM-Newton data, the authors have studied for the first time the X-ray emission of the young star clusters HM1 and IC 2944/2948. Low-mass, pre-main sequence objects with an age of a few Myr are detected, as well as a few background or foreground objects. Most massive stars in both clusters display the usual high-energy properties of that kind of objects, though with log(L<sub>x</sub>/L<sub>bol</sub>) apparently lower in HM1 than in IC 2944/2948. Comparing with studies of other clusters, it seems that low S/N at soft energies, due to the high extinction, may the main cause of this difference. In HM1, the two Wolf-Rayet stars show contrasting behaviors: WR89 is extremely bright, but much softer than WR87. It remains to be seen whether wind-wind collisions or magnetically confined winds can explain such emissions. In IC 2944/2948, the X-ray sources concentrate around HD 101205; a group of massive stars to the north of this object appears rather isolated, suggesting that there exist two sub-clusters in the field of view. This tables provides the list of 368 detected X-ray sources in/toward the Cen OB2 association cluster(s) IC 2944/2948 only, i.e., the 58 X-ray sources detected in/toward the HM1 cluster are not contained herein. This tables lists the basic X-ray source properties (position, count rates, hardness ratios) and their probable optical/infrared counterparts (offset angular distance, name). XMM-Newton has observed IC 2944/2948 for 40 ks on XMM-Newton Rev. 2209 (with the THICK filter). No background flare affected the observation, and no source is bright enough to suffer from pile-up. This table was created by the HEASARC in September 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/555/A83">CDS Catalog J/A+A/555/A83</a> files table3.dat and table4.dat. This is a service provided by NASA HEASARC .
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