| Article in PDF |
"Peremennye Zvezdy", Prilozhenie, vol. 22, N 3 (2022) |
| #1. Astronomical Institute of the Uzbekistan Academy of Sciences, Tashkent, Uzbekistan;
#2. Samarkand State University, Samarkand, Uzbekistan; #3. National University of Uzbekistan, Tashkent, Uzbekistan; #4. State Space Corporation "Roscosmos", Moscow, Russia. |
| ISSN 2221–0474 | DOI: 10.24412/2221-0474-2022-3 |
Received: 27.07.2022; accepted: 11.11.2022
(E-mail for contact: boa@astrin.uz)
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Comments:
2. It was not possible to determine the period because only one minimum was observed. JDmin = 2459465.3624.
3. It was not possible to determine the period because only one minimum was observed. JDmin = 2459511.156.Remarks:
We present the results of searching for variable stars in a field in Cassiopea with the center α=23h58m δ=+62°37′ (2000.0) and the field of view of 30′. We did not find any reference to these stars being variable in the available star databases: GCVS (Samus et al. 2017), VSX, ZTF (Chen et al. 2020), and ASAS-SN Variable Stars Database.
Observations were carried out at the Maidanak Astronomical Observatory of the Astronomical Institute of the Academy of Sciences of the Republic of Uzbekistan (Ehgamberdiev 2018) using the 0.5-meter AMT-1 telescope with Mathis Instruments MI-750/1000 equatorial fork mount equipped with an Apogee Alta U16M (4K×4K) CCD camera. The physical size of a CCD pixel is 9 microns. We used 2×2 binning, which corresponds to 0.907 ′′/pixel, and the field of view of 30.9′×30.9′. The exposure times were 180 seconds in the Bessel R filter. The temperature of the camera was set to –15°C. Calibration images as bias, dark and flat were also obtained for each observational date. Observations were obtained during the period from September 5 to October 30, 2021. The total number of observation nights was 28 during which 2593 images were taken.
All images were processed with master bias, dark, and flat frames using standard IRAF packages. We rejected low-quality images, and the final sample contained 2514 images. The VaST (Variability Search Toolkit) software package (Sokolovsky and Lebedev 2018) was used to search for variable stars.
To derive periods we used period search tool by Dr. K.V. Sokolovsky who incorporated it in his VaST package.
Acknowledgments: We are grateful to the staff of the Maidanak Astronomical Observatory for their efforts to support observations.References:
Chen, X., Wang, S., et al., 2020, Astron. J. Suppl. Ser., 249, 18
Ehgamberdiev, Sh., 2018, Nature Astronomy, 2, 349
Samus, N.N., Kazarovets, E.V., Durlevich, O.V., Kireeva, N.N., Pastukhova, E.N., 2017, Astron. Rep., 61, No. 1, 80
Sokolovsky, K. V., Lebedev, A. A., 2018, Astron. and Computing, 22, 28
