New Eclipsing Binaries in the OGLE-II Database (Part 1). The Carina Galactic Disk Fields

S. Huemmerich^#1,2, K. Bernhard^#1,3

#1. Bundesdeutsche Arbeitsgemeinschaft fuer Veraenderliche Sterne e.V. (BAV), Berlin, Germany; #2. Braubach, Germany; #3. Linz, Austria

Received:   15.06.2012;   accepted:   30.10.2012
(E-mail for contact: ernham@rz-online.de)

Comments:


1. MinII = 16.83. J – K = 0.940 (2MASS).

2. MinII = 16.85. J – K = 0.509 (2MASS). The K magnitude in the 2MASS catalogue is an upper limit or has a very poor quality.

3. MinII = 16.36. J – K = 0.831 (2MASS). Eccentric system; secondary eclipse at phase 0.45.

4. MinII = 16.12. J – K = 0.469 (2MASS).

5. MinII = 14.88. J – K = 0.414 (2MASS).

6. MinII = 16.19. J – K = 0.690 (2MASS). Shows O'Connell effect.

7. MinII = 16.71. J – K = 0.912 (2MASS).

8. MinII = 15.87. J – K = 0.498 (2MASS).

9. MinII = 14.28. J – K = 0.543 (2MASS).

10. MinII = 16.47. J – K = 0.575 (2MASS).

11. MinII = 16.09. J – K = 0.470 (2MASS).

12. MinII = 16.90. J – K = 0.772 (2MASS).

13. MinII = 16.51. J – K = 0.916 (2MASS).

14. MinII = 14.23. J – K = 0.462 (2MASS).

15. MinII = 16.45. J – K = 0.729 (2MASS). The K magnitude in the 2MASS catalogue is an upper limit or has a very poor quality.

16. MinII = 15.39. J – K = 0.768 (2MASS).

17. MinII = 15.00. J – K = 0.395 (2MASS).

18. MinII = 15.91. J – K = 0.662 (2MASS).

19. MinII = 16.50. J – K = 0.656 (2MASS).

20. MinII = 16.90. J – K = 1.054 (2MASS).

Remarks:
The publicly available data of the OGLE-II database (http://ogledb.astrouw.edu.pl/~ogle/photdb/) was searched for unrecorded eclipsing binaries. Only the lightcurves of objects with the following parameters were investigated:

number of good points, Ngood>=300;
percentage of good points, Pgood>=80;
standard deviation of I magnitude, Isig>=0.04;
median I magnitude, Imed<=17;
median error of I magnitude, Imederr<0.015.


Part 1 covers the OGLE-II (Szymański 2005, Udalski et al. 1997) Carina Galactic Disk Fields (CAR_SC1, CAR_SC2, CAR_SC3), from which the specified search returned 20 objects. All stars were checked against the Strasbourg CDS Vizier service and the International Variable Star Index for pre-existence in variability catalogues.

Amplitudes and periods were derived using the Period04 code (Lenz & Breger 2005). Astrometric positions were taken from the 2MASS catalogue (Skrutskie et al. 2006); near-infrared color indices from the 2MASS catalogue are presented in the Comments.

Acknowledgements: This publication makes use of the SIMBAD and VizieR databases operated at the Centre de Données Astronomiques (Strasbourg) in France, of the International Variable Star Index (AAVSO), and of the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

References:
Lenz, P., Breger, M., 2005, Comm. in Asteroseismology, 146, 53
Skrutskie, M.F., Cutri, R.M., Stiening, R., et al., 2006, Astron. J, 131, 1163
Szymański, M. K., 2005, Acta Astron., 55, 43
Udalski, A., Kubiak, M., Szymanski, M., 1997, Acta Astron., 47, 319