Article in PDF |
"Peremennye Zvezdy", Prilozhenie, vol. 10, N 6 (2010) |
ISSN 2221–0474 |
Received: 5.02.2010; accepted: 16.02.2010
(E-mail for contact: khruslov@bk.ru)
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Comments:
1. X-ray source 1RXS J010544.6+332335. B-V = 1.185 (Tycho2), J-H = 0.595 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
2. J-H = 0.552 (2MASS).
3. J-H = 0.612 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
4. J-H = 0.648 (2MASS). P = 30.6 d is not excluded. The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
5. B-V = -0.076 (Tycho2), J-H = 0.139 (2MASS).
6. J-H = 0.633 (2MASS).
7. B-V = 0.576 (Tycho2), J-H = 0.554 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
8. B-V = 1.081 (Tycho2), J-H = 0.532 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
9. J-H = 0.745 (2MASS). M-m = 0.40 P.
10. MinII = 14.0:. J-H = 0.593 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
11. MinII = 11.43. J-H = 0.534 (2MASS), B-V = 0.957 (Tycho2). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
12. J-H = 0.529 (2MASS). Amplitude varies. P = 1.39 d is not excluded.
13. J-H = 0.497 (2MASS). P = 0.93733 d is possible.
14. X-ray source 1RXS J143213.2+453621. J-H = 0.528 (2MASS), B-V = 1.224 (Tycho2). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
15. X-ray source 1RXS J161046.9+611218. J-H =0.587. The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
16. X-ray source 1RXS J162658.6+532407. J-H = 0.515 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
17. X-ray source 1RXS J170157.5+073329. B-V = 0.527 (Tycho2), J-H = 0.360 (2MASS). 11.65 - 11.9 (V, ASAS-3). Not listed in the ASAS catalog of variable stars (Pojmanski 2002). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.
18. X-ray source 1WGA J2252.7+3737. The color index B-V = 2.329 (Tycho2) is probably wrong. J-H = 0.562 (2MASS). The ROTSE data with photometric correction flags (usually rejected) were kept for the analysis.Remarks:
I present the discovery of 18 new periodic variables. The BY Dra classification of many stars in the list is based on their small variability amplitudes, rather large color indices, characteristic periodicity, and X-ray identifictations for some of them.
My search for variables was carried out in the publicly available data of the Northern Sky Variability Survey (NSVS, Wozniak et al. 2004; also see http://skydot.lanl.gov/nsvs). These observations were analyzed using the period-search software developed by Dr. V.P. Goranskij for Windows environment. The coordinates were drawn either from the Tycho-2 or from the 2MASS catalogs.References:
Pojmanski, G., 2002, Acta Astronomica, 52, 397
Wozniak, P.R., Vestrand, W.T., Akerlof, C.W., et al., 2004, Astron. J., 127, 2436