A Study of Six Variable Stars

E. V. Kazarovets, E. N. Pastukhova
Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia

Received:   16.11.2010;   accepted:   25.11.2010
(E-mail for contact: helene@inasan.ru, pastukhova@sai.msu.ru)

Comments:


1. MinII 14.20 (R). The star's variability was announced by Nicholson et al. (2005) who published a wrong period (0.3217d).

2. This star was discovered by Nicholson and Whiting (2006) as an SRB variable without light elements. The ASAS-3 range is for the combined brightness of the Mira and its neighbor.

3. M-m = 0.33P. This star was discovered by Hanley (1942) who did not provide light elements.

4. Not identical to QY Ara. HV 8945 was discovered by Luyten (1935) who announced no light elements and found, upon our request, by D. Williams on Harvard plates. A finding chart for this variable has never been published. R = 15.6 on the USNO Archive image of 1991.5852.

5. This star was discovered by Luyten (1937). No light elements and no finding chart were published for this variable. Now we have recovered this variable. R = 16.6 on the USNO Archive image of 1992.4230. The ASAS-3 range is for the combined brightness of the Mira and its neighbor. Identical to Mis V1286.

6. M-m = 0.11P. A wrong period (0.33361d) was given by Wils et al. (2006).

Remarks:
During our work on preparation of the 80-th Name List of Variable Stars, we checked several poorly studied variables and found new light elements for them.

We could study the variables thanks to the publicly available electronic archives of CCD observations of the ASAS-3 project (Pojmanski 2002), ROTSE1/NSVS project (Wozniak et al. 2004), and to images of the US Naval Observatory Image and Catalogue Archive (http://www.nofs.navy.mil/data/FchPix/). The variable NSV 11227 suspected by Luyten (1937) was recovered in the course of this study.

Acknowledgments: Our studies are supported by grants from the Russian Foundation for Basic Research (grant No. 08-02-00375) and by the Program "Origin and Evolution of Stars and Galaxies" of the Presidium of Russian Academy of Science. Thanks are due to D. Williams for providing finding charts for a number of Harvard variable stars.

References:
Hanley, C.M., 1942, Harvard Observ. Annals, 109, 15
Luyten, W.J., 1935, Astron. Nachr., 256, 325
Luyten, W.J., 1937, Astron. Nachr., 261, 451
Nicholson, M., Sutherland, J., Sutherland, C., 2005, Open Europ. J. Var. Stars, No. 12
Nicholson, M., Whiting, E., 2006, Open Europ. J. Var. Stars, No. 38
Pojmanski, G., 2002, Acta Astron., 52, 397
Wils, P., Lloyd, C., Bernhard, K., 2006, Mon. Notic. Roy. Astron. Soc., 368, 1757
Wozniak, P.R., Vestrand, W.T., Akerlof, C.W., et al., 2004, Astron. J., 127, 2436