New Variable Stars in Andromeda

T. Kryachko^#1, A. Samokhvalov^#2, S. A. Korotkiy^#3

#1. Astrotel Observatory, Karachay-Cherkessia, Russia; #2. Surgut, Russia; #3. Ka-Dar Scientific Center and Public Observatory, Moscow, Russia

Received:   24.11.2008;   accepted:   8.12.2008
(E-mail for contact: bredfild@mail.ru, sav@surgut.ru, astro_stas@mail.ru)

Comments:
1. We observed six primary minima: HJD 2454712.3808, 2454713.5038, 2454774.2700, 2454774.5549, 2454776.2386, 2454776.5200. Min II = 17.36.

2. We observed four primary minima: HJD 2454712.2847, 2454713.5099, 2454776.2531, 2454776.5584. Min II = 17.52.

3. We observed five primary minima: HJD 2454713.3051, 2454714.3669, 2454773.3070, 2454776.4822, 2454778.5956. Min II = 16.72.

4. We observed three primary minima: HJD 2454713.3508, 2454774.2818, 2454778.5807. Min II = 14.57. O`Connell effect.

5. We observed eight primary minima: HJD 2454712.5449, 2454713.4036, 2454714.2727, 2454773.3661, 2454774.2335, 2454775.5306, 2454776.3988, 2454778.5484. Min II = 14.70.

6. We observed eight primary minima: HJD 2454711.3850, 2454712.3173, 2454713.2485, 2454713.5593, 2454773.2580, 2454774.1900, 2454776.3647, 2454778.5448. Min II = 15.99.

7. We observed three primary minima: HJD 2454712.2955, 2454713.3350, 2454714.3863. Min II = 16.17.

8. Two observed primary minima: HJD 2454713.4729, 2454776.3105. Min II = 14.23. O`Connell effect.

9. We observed five primary minima: HJD 2454712.3390, 2454713.3474, 2454773.2665, 2454774.2794, 2454776.2840. Min II = 16.38.

10. We observed five maxima: HJD 2454712.3354, 2454713.3037, 2454713.4459, 2454714.4115, 2454773.2268.

11. We observed five primary minima: HJD 2454713.2543, 2454773.2084, 2454774.3713, 2454775.5435, 2454776.3241. Min II = 14.06.

12. Two observed primary minima: HJD 2454712.2646, 2454775.5870. Min II = 12.25. This low-amplitude variable was also observed by ROTSE-I/NSVS (NSVS 3971176, Wozniak et al. 2004). The NSVS data are not in agreement with our period. The period of 0.3272 days looks suitable both for our and NSVS observations, but the phased light curve for our data plotted using this period looks much worse than for P = 0.32978 days.

Remarks:
During observations of the field of the cataclysmic variable star OT J020025.4+441019 (Kryachko et al. 2008), we discovered 12 new variable stars. Our observations were carried out at the Astrotel-Caucasus observatory using a 80-mm ED-refractor, equipped with an unfiltered SBIG ST-2000XM CCD camera. In total, 564 images with 5-minute exposures were obtained on JD 2454711 - 2454778. Besides, 215 images with 2-minute exposures were obtained on JD 2454713. For basic reductions for dark current, flat fields, and bias, we used the MaxIm DL software. For search and photometry of new variable stars, we applied the VaST software by Sokolovsky and Lebedev (2005). The comparison star was USNO-B1.0 1341-0037983 (01:58:00.19, +44:07:33.5, (J2000), R1 = 13.64, R2 = 13.61). Our unfiltered magnitudes were calibrated assuming Rcomp = 13.625 for the comparison star. Coordinates of the variable stars in the table were drawn from the 2MASS catalogue. Our observations were analyzed using the Peranso software (www.peranso.com).

References:
Kryachko, T., Korotkiy, S., Denisenko, D., Satovskiy, B., 2008, vsnet-alert, 10478
Sokolovsky, K., Lebedev, A., 2005, in 12th Young Scientists' Conference on Astronomy and Space Physics, Kyiv, Ukraine, April 19-23, 2005, eds.: Simon, A.; Golovin, A., p.79
Wozniak, P.R., Vestrand, W.T., Akerlof, C.W., et al., 2004, Astron. J., 127, 2436