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Astrometry of OGLE-III data

Catalog of Stellar Proper Motions toward OGLE-III Magellanic Cloud Fields

We present a catalog of proper motions measured for stars in the direction of Magellanic Clouds including 47 Tuc (NGC104) globular culster. For over 6.2 million stars within the brightness range 12<I<19 mag proper motions are provided. Statistical uncertainties are below 0.5 mas/yr for stars brighter than 18.5 mag. These proper motions allow selection of 440 000 Galactic foreground stars. For over 110 000 stars also parallaxes are presented with uncertainties down to 1.6 mas.

The proper motions can be used to construct reduced proper motion diagram shown below. It allows both separation of white dwarfs and distinguishing main sequence stars belonging to disk and halo populations.

Reduced proper motion diagram

In total, about 270 white dwarfs were selected. The catalog was searched for common proper motion binaries what resulted in the discovery of over 500 candidate systems including a pair of white dwarfs. The proper motion of 47 Tuc was measured and compared to previous estimates. Only the Hubble Space Telescope measurement was significantly better than ours. The proper motions of variable stars are presented separately. We question the existance of a subgroup of blue variables in the LMC claimed by other authors. As an example we use the catalog to search for stars located in the classical Cepheid instability strip, which do not pulsate. FTP site.

PLEASE cite the following paper when using the data or referring to these OGLE results:
Poleski et al., 2012, Acta Astron., 62, 1 (arXiv:1203.2649)

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.

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