Received: 14.10.2010; accepted: 22.11.2010
(E-mail for contact: Ekaterina.Avvakumova@usu.ru)
|The variability of NOMAD-1 1127-0027360 was discovered on frames obtained during
observations of the gamma-ray burst GRB100901a with telescopes of the MASTER robotic
net (Lipunov et al.
2010) (Tunka Valley; Kourovka astronomical observatory; Kislovodsk solar station)
on September 1 - 2, 2010. Completely identical MASTER II telescopes, each of
them consisting of two parallel optical telescopes on the same mount (40 cm
aperture, 1:2.5 focal ratio), are
installed at all three locations. They permit to take two simultaneous images in
The telescopes are equipped with Apogee Alta U16 CCD cameras (Kodak KAF16000
chip, Peltier cooled). Additional observations of the object were carried out
at Kourovka astronomical observatory on September 2 - 4, 2010. Instrumental I and
R filters were used.
The reductions of CCD frames were carried out with the IRAF package (Tody 1993). We did not transform our observations to a standart photometric system. Our I-band observations cover both the primary and the secondary minimum as well as both maxima. The secondary maximum was not covered with our R-band observations. We suggest that the star is an EB eclipsing variable.
The period was determined using the FAMIAS software package developed in the framework of the FP6 European Coordination Action HELAS (Zima 2008).
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 contract No. 02.740.11.0249).
|Lipunov, V., Kornilov, V., Gorbovskoy, E., et al., 2010, Advances in
Astronomy, 2010, Article ID 349171
Tody, D., 1993, A.S.P. Conference Ser., 52, 173
Zima, W., 2008, Comm. in Asteroseismology, 155, 17
The I-band light curve.