Moscow Digital Variables. II

D. Kolesnikova^#1, K. V. Sokolovsky^#1,#2, N. N. Samus^#3,#1, S. V. Antipin^#1,#3

#1. Sternberg Astronomical Institute; #2. Astro Space Center of the Lebedev Physical Institute, Russian Academy of Sciences; #3. Institute of Astronomy, Russian Academy of Sciences;

Received:   22.12.2006;   accepted:   5.02.2007
(E-mail for contact: poocha@aport2000.ru)

Comments:
3. MinII 15.6.

5. MinII 15.5.

6. NSVS 8710529. NSVS data confirms variability.

7. NSVS 8710609. NSVS data confirms variability. Possibly SRB with a period about 90 days.

8. MinII 14.8.

11. MinII 16.4.

12. White. The presence of a small compact nebula can be suspected from Aladin images.

14. 1RXS J212806.5+365412 = GSC 2716-01758.

15. MinII 14.9.

Remarks:
We present the results of our second pilot project of variable-star search using scanned photographic plates. Two square 1.5-to-1.5-degree regions in Cygnus, centered at 21h24m44s, +36deg21'51" and 20h54m24s, +41deg05'38" (J2000), were studied. 175 photographic plates of these fields were taken with the 40-cm astrograph in Crimea, they cover 20 years between 1975 and 1995. The plates were scanned by one of the authors (D. Kolesnikova) at 2540 dpi resolution with the Sternberg Institute's CREO EverSmart Supreme II flatbed scanner. 16 bit-per-channel TIFF images produced by the scanner were converted to FITS format by means of custom software developed by A. Lebedev & K. Sokolovsky (available online at ftp://scan.sai.msu.ru/pub/software/tiff2fits/). Further analysis was done in VAST software (Sokolovsky, Lebedev, 2005) which is based on the well-known SExtractor by Bertin (2006). A total of 18 variable objects were detected, three of them were previously reported as variable stars by different authors. For V1219 Cyg (type IN, Hoffmeister, 1967) and NSVS 2122045+355634 (type L, Wozniak et al., 2004), our data is fully consistent with the existing classification, so we drop them from further consideration. The data is available upon request. The third star (GSC 03171-00761, Otero et. al., 2004) will be discussed in detail in a separate paper. Properties of 15 previously unreported variables are presented in the Table above. All magnitudes in this work were calibrated using photographic blue magnitudes of neighboring USNO-A2.0 stars (Monet et al., 1998). Time series analysis was done with WinEffect software, developed by V. Goranskij.

Acknowledgments: The authors would like to thank A. Lebedev, S. Nazarov, and D. Nasonov for their contribution to development of VAST. This research has made use of Aladin interactive sky atlas and SIMBAD database, operated at CDS, Strasbourg, France. N. Samus, S. Antipin and K. Sokolovsky are grateful to RFBR grants 05-02-16289 and 05-02-16688.

References:
Bertin, E., 2006, "SExtractor v2.5 User's manual" (http://terapix.iap.fr/rubrique.php?id_rubrique=91/)
Hoffmeister, C., 1967, Astronomische Nachrichten, 290, 43
Monet, D., Bird, A., Canzian, B., et al., 1998, USNO-A2.0, A Catalog of Astrometric Standards (U.S. Naval Observatory, Washington, DC)
Otero, S.A., Wils, P., Dubovsky, P.A., 2004, IBVS, No. 5570
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 (VAST: http://saistud.sai.msu.ru/vast)
Wozniak, P.R., Williams, S.J., Vestrand, W.T., Gupta, V., 2004, Astronomical Journal, 128, 2965