Monitoring the Period Variation of KR Cyg Eclipsing Binary

Mehmet Geldi; Kübra Çalışkan; Esin Sipahi

doi:10.26650/PAR.2025.00002

Monitoring the Period Variation of KR Cyg Eclipsing Binary

Abstract

This study examines the period variation of the eclipsing binary system KR Cyg, a near-contact binary characterized by its short orbital period and significant stellar interactions. The precise orbital parameters of the system have been determined through light curve data collected periodically since 1999 and were published in our previous studies. Additionally, minimum light observations have been continuously monitored to analyze the period variation of the system. In our earlier work, the masses of the primary and secondary components were determined as 2.88 ± 0.20𝑀⊙ and 1.26 ± 0.07𝑀⊙, with corresponding radii of 2.59 ± 0.06𝑅⊙ and 1.80 ± 0.04𝑅⊙. The bolometric albedo and effective temperature of the less massive star were also investigated, and deviations caused by mutual illumination effects were identified. These results provide valuable insights into the evolutionary status of KR Cyg and shed light on the dynamic processes that occur in near-contact binary systems. Using updated eclipse timings, an (O-C) diagram was constructed, revealing both long-term trends and periodic oscillations. These cyclical variations are thought to indicate the presence of a tertiary component affecting the system via the light-time effect. Additional observations and modeling are recommended to confirm the tertiary hypothesis and further refine the parameters of the system.

Keywords

References

Al-Naimiy H. M. K., Al-Mahdi H. A., Al-Sikab A. O., Mutter A. A., 1985, Ap&SS, 117, 351 google scholar
Cai J.-T., Yu Y.-X., Hu K., Xiang F.-Y., 2019, Research in Astronomy and Astrophysics, 19, 106 google scholar
Erdem A., Aliçavuş F., Soydugan F., Doğru S. S., Soydugan E., Çiçek C., Demircan O., 2011, New Astron., 16, 498 google scholar
Gaposchkin S., 1953, Annals of Harvard College Observatory, 113, 67 google scholar
Giuricin G., Mardirossian F., Mezzetti M., 1983, A&AS, 54, 211 google scholar
Hill G., Hilditch R. W., Younger F., Fisher W. A., 1975, Mem. RAS, 79, 131 google scholar
Irwin J. B., 1959, AJ, 64, 149 google scholar
Kholopov P. N., 1985, General Catalogue of Variable Stars. Nauka, Moscow google scholar

Koch R. H., 1973, AJ, 78, 410 google scholar
Lassovszky K., 1936, Astronomische Nachrichten, 258, 93 google scholar
Nekrasova S., 1945, Izvestiya Glavnoj Astronomicheskoj Observatorii v Pulkove, 16, 27 google scholar
Paschke A., Brat L., 2006, Open European Journal on Variable Stars, 23, 13 google scholar
Ricker G. R., et al., 2015, Journal of Astronomical Telescopes, Instru-ments, and Systems, 1, 014003 google scholar
Schneller H., 1931, Astronomische Nachrichten, 243, 335 google scholar
Schneller H., 1932, Astronomische Nachrichten, 245, 43 google scholar
Shaw J. S., 1990, in Active Close Binaries Proceedings, NATO Ad-vanced Study Institute. p. 241 google scholar
Sipahi E., 2012, New Astron., 17, 383 google scholar
Sipahi E., Gülmen Ö., 2004, Ap&SS, 293, 307 google scholar
Sipahi E., Tas G., 2006, in Solomos N., ed., American Institute of Physics Conference Series Vol. 848, Recent Advances in Astron-omy and Astrophysics. AIP, pp 437-441, doi:10.1063/1.2348016 google scholar
Sipahi E., Çakirli Ö., Ibanoglu C., 2013, Rev. Mex. Astron. Astrofis., 49, 25 google scholar
Tsesevich V. P., 1954, Odessa Izvestiya, 4, 263 google scholar
Tvardovskyi D. E., Marsakova V. I., 2015, Advances in Astronomy and Space Physics, 5, 75 google scholar
Vetesnik M., 1965, Bulletin of the Astronomical Institutes of Czechoslovakia, 16, 326 google scholar
Wachmann A. A., 1948, Astronomische Abhandlungen, Erganzung-shefte zu den Astronomischen Nachrichten, 11 google scholar
Wilson R. E., Rafert J. B., 1980, A&AS, 42, 195 google scholar
Zasche P., et al., 2023, MNRAS, 520, 3127 google scholar

Details

Primary Language

English

Subjects

Classical Physics (Other)

Journal Section

Research Article

Authors

Mehmet Geldi
0009-0004-0863-9957
Türkiye

Kübra Çalışkan This is me
0009-0007-7857-6850
Türkiye

Esin Sipahi This is me
Türkiye

Publication Date

June 24, 2025

Submission Date

April 20, 2025

Acceptance Date

May 23, 2025

Published in Issue

Year 2025 Volume: 3 Number: 1

DOI

https://doi.org/10.26650/PAR.2025.00002

IZ

https://izlik.org/JA73FM45GA

Cite

RIS / Bibtex

APA

Geldi, M., Çalışkan, K., & Sipahi, E. (2025). Monitoring the Period Variation of KR Cyg Eclipsing Binary. Physics and Astronomy Reports, 3(1), 21-28. https://doi.org/10.26650/PAR.2025.00002

AMA

1.Geldi M, Çalışkan K, Sipahi E. Monitoring the Period Variation of KR Cyg Eclipsing Binary. Physics and Astronomy Reports. 2025;3(1):21-28. doi:10.26650/PAR.2025.00002

Chicago

Geldi, Mehmet, Kübra Çalışkan, and Esin Sipahi. 2025. “Monitoring the Period Variation of KR Cyg Eclipsing Binary”. Physics and Astronomy Reports 3 (1): 21-28. https://doi.org/10.26650/PAR.2025.00002.

EndNote

Geldi M, Çalışkan K, Sipahi E (June 1, 2025) Monitoring the Period Variation of KR Cyg Eclipsing Binary. Physics and Astronomy Reports 3 1 21–28.

IEEE

[1]M. Geldi, K. Çalışkan, and E. Sipahi, “Monitoring the Period Variation of KR Cyg Eclipsing Binary”, Physics and Astronomy Reports, vol. 3, no. 1, pp. 21–28, June 2025, doi: 10.26650/PAR.2025.00002.

ISNAD

Geldi, Mehmet - Çalışkan, Kübra - Sipahi, Esin. “Monitoring the Period Variation of KR Cyg Eclipsing Binary”. Physics and Astronomy Reports 3/1 (June 1, 2025): 21-28. https://doi.org/10.26650/PAR.2025.00002.

JAMA

1.Geldi M, Çalışkan K, Sipahi E. Monitoring the Period Variation of KR Cyg Eclipsing Binary. Physics and Astronomy Reports. 2025;3:21–28.

MLA

Geldi, Mehmet, et al. “Monitoring the Period Variation of KR Cyg Eclipsing Binary”. Physics and Astronomy Reports, vol. 3, no. 1, June 2025, pp. 21-28, doi:10.26650/PAR.2025.00002.

Vancouver

1.Mehmet Geldi, Kübra Çalışkan, Esin Sipahi. Monitoring the Period Variation of KR Cyg Eclipsing Binary. Physics and Astronomy Reports. 2025 Jun. 1;3(1):21-8. doi:10.26650/PAR.2025.00002