Abstract
The paper presents the results of studying light curves of the star HD 168443 obtained from the ground-based and space photometric observations within the ASAS, KWS surveys, and the Hipparcos mission from 1990 to 2020. During 30 years of observations, the average annual brightness of the star remained constant within the measurement errors, the mean V-value was 6m.96. Using the dense data series in 2007–2009, the photometric period of 34.7 days was found, and the low-amplitude brightness variability was studied with this period. We determined epochs and amplitude of rotational modulation produced by the development of active regions. These parameters do not change during 2–5 rotations of the star. The amplitude of the rotational modulation increases in 2007 before the epoch of maximum brightness. The star was the brightest in 2009, its V-magnitude was 6m.92. The location of starspots on the surface of the star during these epochs is also considered.
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ACKNOWLEDGMENTS
The authors are grateful to the referees for constructive comments and recommendations to the article, as well as to E.P. Pavlenko for discussion of some methods of periodicity analysis. In our research we have used information from the SIMBAD database, photometric data from Hipparcos, the International Variable Star Index (VSX) database, the Kamogata–Kiso–Kyoto Wide-Field Survey. The authors are thankful to all the staff providing the replenishment of these databases and access to them, as well as to the developers of the AVE software package.
Funding
This work was supported by ongoing institutional funding. No additional grants to carry out or direct this particular research were obtained.
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Bondar’, N.I., Shlyapnikov, A.A. A Search for Low-amplitude Periodic Brightness Variations in HD 168 443. Geomagn. Aeron. 63, 1277–1284 (2023). https://doi.org/10.1134/S0016793223080054
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DOI: https://doi.org/10.1134/S0016793223080054