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Pulsations of the AS Cam Eclipsing Binary in TESS Light Curves

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Abstract

An analysis of TESS satellite observations of the AS Cam eclipsing binary has shown that the light of this source pulsates at two frequencies: \({{\nu }_{1}} = 0.7556\) days–1 and \({{\nu }_{2}} = 0.8658\) days–1 with the amplitudes \({{A}_{1}} = 0_{.}^{{\text{m}}}0110\) and \({{A}_{2}} = 0_{.}^{{\text{m}}}0087,\) correspondingly. Such variations are typical for slowly pulsating B-type stars. We modeled the light curves of AS Cam obtained from 1968 to 2019 to confirm the discovery of a gradual increase in the orbit eccentricity of the system by approximately 0.018 over 50 years. A third light, as one of the light curve solution parameters, on average, amounts to approximately 4% of the total luminosity of the system. For AS Cam this would correspond to an F8–F9-type suggested third body—a main sequence star, the presence of which follows from the light equation of the system. If the third light is a result of a random overlapping of a star unrelated to AS Cam, then the third body may turn out to be a degenerate object or a close binary system. The extremely slow apsidal motion in this system (compared to the value predicted by the standard theory) can be explained by the gravitational influence of a third body with a mass of about \(1.2{{M}_{ \odot }}\) and an orbital inclination of about \(70\) with respect to the image plane.

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Notes

  1. See the B.R.N.O. database, http://var2.astro.cz/ocgate/?lang=en.

  2. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html.

  3. Exotic alternatives like a revision of the gravity theory are not mentioned. The general theory of relativity gives estimates of the apsidal line rotation velocity that coincide practically ideally with the observed values for most systems (Baroch et al., 2021), with the exception of a few, AS Cam included.

REFERENCES

  1. D. Baroch, A. Giménez, I. Ribas, et al., Astron. and Astrophys. 649, id. A64 (2021).

  2. T. Borkovits, E. Forgács-Dajka, and Z. Regály, ASP Conf. Ser. 333, 128 (2005).

  3. T. Borkovits, E. Forgács-Dajka, and Z. Regály, Astron. and Astrophys. 473 (1), 191 (2007).

    Article  ADS  Google Scholar 

  4. Z. Bozkurt and Ö. L. Değirmenci, ASP Conf. Ser. 335, 277 (2005).

  5. Z. Bozkurt and Ö. L. Değirmenci, Monthly Notices Royal Astron. Soc. 379 (1), 370 (2007).

    Article  ADS  Google Scholar 

  6. M. Breger, Delta Scuti Star Newsletter 2, 21 (1990).

    ADS  Google Scholar 

  7. A. Claret, A. Giménez, D. Baroch, et al., arXiv: 2107.10765 (2021).

  8. G. N. Dryomova and V. V. Dryomov, Research Astron. Astrophys. 19 (3), id. 035 (2019).

  9. R.W. Hilditch, Observatory 89, 143 (1969).

    ADS  Google Scholar 

  10. R. W. Hilditch, Memoirs of the Royal Astronomical Society 76, 1 (1972a).

    ADS  Google Scholar 

  11. R. W. Hilditch, Publ. Astron. Soc. Pacific 84 (500), 519 (1972b).

    Article  ADS  Google Scholar 

  12. K. F. Khaliullin, S. A. Khodykin, and A. I. Zakharov, Astrophys. J. 375, 314 (1991).

    Article  ADS  Google Scholar 

  13. K. F. Khaliullin and V. S. Kozyreva, Astrophys. and Space Sci. 94 (1), 115 (1983).

    Article  ADS  Google Scholar 

  14. A. I. Khaliullina and K. F. Khaliullin, Sov. Astron. 28, 228 (1984).

    ADS  Google Scholar 

  15. Y. Kozai, Astron. J. 67, 591 (1962).

    Article  ADS  MathSciNet  Google Scholar 

  16. V. Kozyreva, A. Kusakin, and A. Bogomazov, Research Astron. Astrophys. 18 (1), id. 010 (2018).

  17. V. S. Kozyreva and L. A. Bagaev, Astronomy Letters 35 (7), 483 (2009).

    Article  ADS  Google Scholar 

  18. V. S. Kozyreva and A. I. Zakharov, Astronomy Letters 27 (11), 712 (2001).

    Article  ADS  Google Scholar 

  19. V. S. Kozyreva, A. I. Zakharov, and K. F. Khaliullin, Inform. Bull. Variable Stars 4690, 1 (1999).

    ADS  Google Scholar 

  20. M. L. Lidov, Planetary Space Sci. 9 (10), 719 (1962).

    Article  ADS  Google Scholar 

  21. K. Pavlovski, J. Southworth, and V. Kolbas, Astrophys. J. 734 (2), L29 (2011).

    Article  ADS  Google Scholar 

  22. G. R. Ricker, J. N. Winn, R. Vanderspek, et al., SPIE Conf. Proc. 9143, id. 914320 (2014).

  23. N. I. Shakura, Pis’ma Astron. Zh. 11, 536 (1985).

    ADS  Google Scholar 

  24. R. F. Stellingwerf, Astrophys. J. 224, 953 (1978).

    Article  ADS  Google Scholar 

  25. W. Szewczuk, P. Walczak, and J. Daszy\(\acute{n}\)ska-Daszkiewicz, Monthly Notices Royal Astron. Soc. 503, 5894 (2021).

    Article  ADS  Google Scholar 

  26. A. I. Zakharov, K. F. Khaliullin, and S. A. Khodykin, Astron. Tsirkular, No. 1529, 13 (1988).

    Google Scholar 

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ACKNOWLEDGMENTS

This research has made use of the SIMBAD database (operated at CDS, Strasbourg, France) and of NASA’s Astrophysics Data System. Some of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). The authors are grateful to the anonymous referee for comments that helped improve the paper.

Funding

This research is funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (project no. AP09259383).

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Correspondence to V. S. Kozyreva.

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Translated by E. Chmyreva

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Kozyreva, V.S., Kusakin, A.V., Bogomazov, A.I. et al. Pulsations of the AS Cam Eclipsing Binary in TESS Light Curves. Astrophys. Bull. 76, 424–434 (2021). https://doi.org/10.1134/S1990341321040088

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