Optical position and proper motion for X-ray sources southeastern of the Ophiucus molecular clouds
Abstract
Here we are interested in defining the optical counterpart and to determine accurate positions and proper motions of approximately three hundred of X-ray sources observed by ROSAT. These sources are distributed in a region at the southeastern of the Ophiuchus molecular cloud complex. This region is specially interesting mainly due to the fact that it contains PMS stars that are "isolated" from molecular clouds. The identification of new PMS stars and the proper motion measurements in this region is important to understand why these stars are far from the molecular clouds and their formation mechanism. The X-ray sources considered here form a list of new possible PMS stars candidates that were selected by using X-ray hardness ratios.
- Publication:
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Journées 2002 - systèmes de référence spatio-temporels. Astrometry from ground and from space
- Pub Date:
- 2003
- Bibcode:
- 2003jsrs...14...31T
- Keywords:
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- X-Ray Sources;
- Positions;
- Proper Motions;
- Molecular Clouds