Astrometry of OGLE-III data

High Proper Motion Stars in the OGLE-III Data for Magellanic Clouds Fields

Previous searches for High Proper Motion (HPM) stars toward Magellanic Clouds examined this sky area in less detail as high stellar density hampers efforts in performing high-quality asrtrometry. We present a new catalog of 549 HPM stars (i.e., ones with proper motion higher than 100 mas/yr) which is based on OGLE-III data for Magellanic Clouds fields. The completeness of our catalog is at least 25% higher than previous catalogs covering Magellanic Clouds.

Proper motions and parallaxes were derived using time-series astrometry. Figure below presents model fits to the data. The star LMC194.6.41 with parallax equal to 91.3 mas is the closest star found. The highest proper motion found is 722 mas/yr.

Exemplary model fits

Using derived parallaxes the color-absolute magnitude diagram was constructed. It allowed selection of 21 white dwarfs and one subdwarf. Other 23 white dwarf candidates were selected among HPM objects with no measurable parallaxes based on color-magnitude diagram. Also 27 common proper motion binaries were found. Full catalog with data description is given on this FTP site.

Color-absolute magnitude diagram
Color-absolute magnitude diagram. Blue symbols indicate white dwarfs.

PLEASE cite the following paper when using the data or referring to these OGLE results:
Poleski et al., 2011, Acta Astron., 61, 199 (arXiv:1110.2178)

Any comments about the data and the form of their presentation are welcome as they can improve the future releases of OGLE astrometric catalogs. Send your messages to this address.