Comments:
1. MinII=18m.83.
2. MinII=15m.83.
3. Primary minimum: HJD(TT) 2455131.5734 ± 0.0005. MinII=16m.80.
4. Infrared colors J-H=0.645, H-K=0.130 and J-K=0.775 (2MASS) are consistent with
the
dK spectral type (Bessell and Brett 1988) and BY classification.
5. O'Connell effect. Primary minima:HJD(TT) | ± |
2455146.6091 | 0.0003 |
2455159.440 |
0.001 |
2455229.3011 | 0.0005 |
2455257.2455 | 0.0007 |
MinII=16m.07.
6. A close pair of two stars, not found in any catalogues separately. The angular
resolution of our telescope is insufficient to determine which of the two stars varies.
Primary minima:HJD(TT) | ± |
2455159.5006 | 0.0007 |
2455191.424 | 0.002 |
MinII=17m.29.
7. Primary minima:HJD(TT) | ± |
2455159.5731 | 0.0003 |
2455205.3694 | 0.0006 |
MinII=15m.61.
8. Primary minima:HJD(TT) | ± |
2455128.5618 | 0.0006 |
2455146.6032 | 0.0003 |
2455159.4917 | 0.0008 |
2455189.4841 | 0.0007 |
MinII=18m.49.
Remarks:
During observations of a field in Taurus, we discovered 8 new variable stars.
Our observations were carried out at the Astrotel-Caucasus observatory using the
300-mm
Ritchey-Chretien telescope, equipped with an unfiltered Apogee Alta U9000 CCD camera.
A total of 612 images with 5-minute exposures were obtained on JD 2455125 - 2455257.
For basic reductions for dark current, flat fields, and bias, we used IRAF routines.
For search and photometry of new variable stars, we applied VaST software by Sokolovsky
and
Lebedev (2005). The comparison star was USNO-A2.0 1050-01424022 = USNO-B1.0 1122-0073209
(
α=04h47m11s.17, δ=+22°15′ 43″.4
J2000, 2MASS); R1=14m.21, R2=14m.35
(USNO-B1.0). Unfiltered magnitudes were calibrated using the comparison star, assuming
Rcomp=14m.28.
The coordinates of the variable stars in the table were drawn from the 2MASS catalogue
(Skrutskie et al. 2006).
For search for periods and epochs of extrema, we use Peranso software (www.peranso.com).
Acknowledgements: We would like to thank S.V. Antipin for helpful
discussion.
References:
Bessell, M.S., Brett, J.M., 1988, PASP, 100, 1134
Skrutskie, M.F., Cutri, R.M., Stiening, R., et al., 2006, AJ, 131, 1163
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