Peremennye Zvezdy

"Peremennye Zvezdy",
Prilozhenie
,
vol. 11, N 27 (2011)

New Variable Stars in the Open Cluster NGC 7129

A. A. Popov, V. V. Krushinsky, E. A. Avvakumova, A. F. Punanova, I. S. Zalozhnih, A. Y. Burdanov
Kourovka Astronomical Observatory of Ural State University, Yekaterinburg, Russia

Received:   19.04.2011;   accepted:   13.07.2011
(E-mail for contact: apopov66@gmail.com)


#NameOtherCoord (J2000)TypeMaxMinSystemPeriodEpoch (JD)typeSpCommentL.CurveFind.ChartData
1 2MASS 21442961+654843821 44 29.62, +65 48 43.9EA:14.7315.11R  other Comm. 1v68.jpgim_v68.pngv68.txt
2 2MASS 21433767+655048921 43 37.67, +65 50 48.9INT:17.8418.34V  other Comm. 2v233.jpgim_v233.pngv233.txt
3 2MASS 21435283+655427721 43 52.84, +65 54 27.7SR:14.1714.30V23.05: other Comm. 3v526.jpgim_v526.pngv526.txt
4 2MASS 21412361+655537721 41 23.62, +65 55 37.7SR:14.6514.97V  other Comm. 4v579.jpgim_v579.pngv579.txt
5 2MASS 21422105+655540521 42 21.06, +65 55 40.5SR:16.0516.24V  other Comm. 5v596.jpgim_v596.pngv596.txt
6 2MASS 21430782+655709521 43 07.82, +65 57 09.5I:13.2613.50I  other Comm. 6v703.jpgim_v703.pngv703.txt
7 2MASS 21421203+660025421 42 12.03, +66 00 25.5INT:16.5117.38V  other Comm. 7v884.jpgim_v884.pngv884.txt
8 2MASS 21405762+660225521 40 57.62, +66 02 25.6SR:13.7814.11V  other Comm. 8v990.jpgim_v990.pngv990.txt
9 2MASS 21405096+660347521 40 50.97, +66 03 47.5SR:12.3012.45V  other Comm. 9v1054.jpgim_v1054.pngv1054.txt
10 2MASS 21395519+660406921 39 55.20, +66 04 07.0EW15.0515.15V0.886962455232.35min Comm. 10v1070.jpgim_v1070.pngv1070.txt
11 2MASS 21425961+660433821 42 59.61, +66 04 33.8INT15.1715.94I4.4: otherK2Comm. 11v1108.jpgim_v1108.pngv1108.txt
12 2MASS 21440634+660423121 44 06.35, +66 04 23.1INT:16.9018.73V  other Comm. 12v1111.jpgim_v1111.pngv1111.txt
13 2MASS 21424705+660457821 42 47.05, +66 04 57.8BY:15.1615.46V1.12672455235.46min Comm. 13v1133.jpgim_v1133.pngv1133.txt
14 2MASS 21431683+660548621 43 16.83, +66 05 48.7INT:15.7916.01I  other Comm. 14v1196.jpgim_v1196.pngv1196.txt
15 2MASS 21430188+660644721 43 01.88, +66 06 44.8INT:14.8915.11I  other Comm. 15v1245.jpgim_v1245.pngv1245.txt
16 2MASS 21425261+660657221 42 52.62, +66 06 57.3INT15.6616.10I  other Comm. 16v1258.jpgim_v1258.pngv1258.txt
17 2MASS 21425349+660805321 42 53.50, +66 08 05.4INT:16.1716.41R  other Comm. 17v1309.jpgim_v1309.pngv1309.txt
18 2MASS 21433182+660850621 43 31.82, +66 08 50.7INT17.5918.65V  other Comm. 18v1350.jpgim_v1350.pngv1350.txt
19 2MASS 21431161+660911421 43 11.61, +66 09 11.5INT16.2816.53V1.70: other Comm. 19v1361.jpgim_v1361.pngv1361.txt
20 2MASS 21432695+660936521 43 26.95, +66 09 36.5IN:14.8914.99I  other Comm. 20v1388.jpgim_v1388.pngv1388.txt
21 2MASS 21432290+661000021 43 22.91, +66 10 00.0LB:15.5716.11I  other  v1412.jpgim_v1412.pngv1412.txt
22 2MASS 21433625+661132921 43 36.25, +66 11 32.9BY:13.4313.57V3.77012455127.67min Comm. 22v1477.jpgim_v1477.pngv1477.txt
23 2MASS 21424283+661228221 42 42.84, +66 12 28.2EB14.4914.74V1.26412455237.12min Comm. 23v1514.jpgim_v1514.pngv1514.txt
24 2MASS 21424023+661328721 42 40.24, +66 13 28.8INT:15.5416.80I  other  v1572.jpgim_v1572.pngv1572.txt
25 2MASS 21413315+662220421 41 33.16, +66 22 20.4INT15.1815.93V  otherK4Comm. 25v1895.jpgim_v1895.pngv1895.txt
26 2MASS 21403066+662603421 40 30.67, +66 26 03.5LB:14.8514.97V  other Comm. 26v2042.jpgim_v2042.pngv2042.txt
27 2MASS 21402965+662644221 40 29.65, +66 26 44.2INT:16.4416.79R  other Comm. 27v2068.jpgim_v2068.pngv2068.txt
28 2MASS 21444647+662701821 44 46.47, +66 27 01.9SR:13.3213.44V  other Comm. 28v2105.jpgim_v2105.pngv2105.txt

Comments:


1. I = 14.38 – 14.72.

2. R = 16.92 – 17.67; I = 15.96 – 16.72.

3. R = 12.77 – 12.89; I = 11.20 – 11.24.

4. R = 13.05 – 13.41; I = 10.84 – 11.02.

5. R = 14.40 – 14.55; I = 12.27 – 12.33.

6. IRAS 21419+6543.

7. R = 15.62 – 16.48; I = 14.86 – 15.39.

8. R = 12.29 – 12.56; I = 10.27 – 10.41.

9. R = 10.85 – 10.97.

10. I = 14.09 – 14.22.

11. X-ray source SS2009 NGC7129-S3-X1. A T Tau variable according to Kun et al. (2009).

12. R = 16.06 – 17.38; I = 14.78 – 16.10.

13. X-ray source SS2009 NGC7129-S3-X2. R = 14.27 – 14.50; I = 13.36 – 13.50.

14. X-ray source SS2009 NGC7129-S3-X9.

15. X-ray source SS2009 NGC7129-S3-X20.

16. X-ray source SS2009 NGC7129-S3-X25. A T Tau variable according to Magakian et al. (2004).

17. X-ray source SS2009 NGC7129-S3-X29. I = 14.89 – 15.07.

18. X-ray source SS2009 NGC7129-S2-X1. A T Tau variable according to Magakian et al. (2004). R = 16.73 – 17.83; I = 15.70 – 16.38.

19. X-ray source SS2009 NGC7129-S3-X30. A T Tau variable according to Kun et al. (2009). R = 15.21 – 15.47; I = 14.10 – 14.26.

20. X-ray source SS2009 NGC7129-S2-X4.

22. X-ray source SS2009 NGC7129-S2-X9. R = 12.83 – 12.96; I = 12.41 – 12.51.

23. O'Connell effect is possible. R = 13.63 – 13.89; I = 12.82 – 13.04.

25. IRAS 21404+6608. A T Tau variable according to Kun et al. (2009). R = 14.37 – 14.94; I = 13.17 – 13.63.

26. R = 13.08 – 13.20; I = 10.93 – 10.99.

27. I = 15.45 – 15.64.

28. I = 10.32 – 10.39.

Remarks:
Photometric observations of the young open cluster NGC 7129 were performed between October 22, 2009 and November 20, 2010 in the Kourovka Astronomical Observatory of Ural State University. We used one of the MASTER robotic telescopes (Lipunov 2004), equipped with the Apogee AltaU16 4096 x 4096 Peltier-cooled CCD camera, its pixel size being 9 x 9 μm. The observations were carried out in the VRI filters of the Johnson–Cousins system. The initial reductions (dark subtraction and flat-fielding) and photometry were performed using the IRAF V2.14 software package. Photometry of 2300 stars was made in a small area (75' x 45') of the frame. The photometric uncertainty was from 0.007 to 0.06 mag for 700 stars with magnitudes from 11 to 16. We found 23 new variable stars and obtained new photometric data for 5 known variable stars, the results are presented in the Table. We also observed the previously known variables V373 Cep, V350 Cep, and Cl NGC7129 SV1 (Semkov 2003), our results are in general agreement with data available for these stars. The suspected variable NSV 13871 showed no brightness variations in excess of photometry errors, i.e. it is found constant within 0.02 mag.

From our observations, we classify three stars as eclipsing binaries of EA, EB, EW types and two stars, as probable BY-type rotating variables by the shape of their light curves. To determine the periods, we used the period-search software developed by Dr. V.P. Goranskij for Windows environment. For classification of the other objects, we use their (J–H) and (H–K) color indices from the 2MASS survey. The stars v233, v884, v1108, v1111, v1196, v1245, v1258, v1309, v1350, v1361, v1388, v1572, v1895, v2068 exhibit a significant infrared excess. They are located in the area of classical T Tau stars in the (J–H) vs (H–K) diagram (Meyer et al. 1997). Five of these stars were previously classified as T Tau variables based on the presence of Hα emission in their spectra (Stelzer & Scholz 2009; Kun et al. 2009; Magakian et al. 2004). We believe that the nine other stars with similar positions in the diagram are also Orion variables. The slowly pulsating stars v526, v579, v596, v990, v1054, v1412, v2042, v2105 are located in the area of giant stars in the (J–H) vs (H–K) diagram. We classified this stars as SR: or LB: variables. Our classification of IN and SR stars is only provisional. Lond series of observations are needed to improve classification of these stars. The star coordinates were taken from the 2MASS catalog. The information on X-ray sources was taken from Stelzer and Scholz (2009). The spectral types are from Kun et al. (2009).

In our light curves, the V magnitudes are plotted as black squares; R magnitudes, as red triangles; and I magnitudes, as blue crosses. DV and DR in the panels are magnitude shifts applied respectively to the V- and R-band data.

Acknowledgements: This study was financially supported by the State Agency for Science and Innovation of the Ministry of Education and Science of the Russian Federation (state contracts No. 02.740.11.0249 and No. 02.740.11.0247), by the State Agency for Education of the Ministry of Education and Science of the Russian Federation (state contracts No. 540 and No. 919).

References:
Kun, M., Balog, Z., Kenyon, S.J., et al., 2009, Astrophys. J. Suppl., 185, 451
Lipunov, V.M., Krylov, A.V., Kornilov, V.G., et al., 2004, Astron. Nachr., 325, 580
Magakian, T.Yu., Movsessian, T.A., Nikogossian, E.H., 2004, Astrophysics, 47, 519
Meyer, M.R., Calvet, N., Hillenbrand, L.A., 1997, Astron. J., 114, 288
Semkov, E.H., 2003, IBVS, No. 5406
Stelzer, B., Scholz, A., 2009, Astron. Astrophys., 507, 227



Main Page | Search
Astronet | SAI | INASAN

Report problems