Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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V608 CASSIOPEIAE: A W UMA-TYPE ECLIPSING BINARY WITH TWO POSSIBLE CIRCUMBINARY COMPANIONS

  • Received : 2021.10.16
  • Accepted : 2021.12.28
  • Published : 2022.02.28
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Abstract

We present the photometric properties of V608 Cas from detailed studies of light curves and eclipse timings. The light curve synthesis indicates that the eclipsing pair is an overcontact binary with parameters of ∆T = 155 K, q = 0.328, and f = 26%. We detected the third light ℓ3, which corresponds to about 8% and 5% of the total systemic light in V and R bands, respectively. Including our 6 timing measurements, a total of 38 times of minimum light were used for a period study. It was found that the orbital period of V608 Cas has varied in some combination of an upward parabola and two periodic variations. The continuous period increase with a rate of +3.99 × 10-7 d yr-1 can be interpreted as a mass transfer from the secondary component to the primary star at a rate of 1.51 × 10-7 M⊙ yr-1. The periods and semi-amplitudes of the two periodic variations are about P3 = 16.0 yr and P4 = 26.3 yr, and K3 = 0.0341 d and K4 = 0.0305 d, respectively. The most likely explanation of both cycles is a pair of light-traveling time effects operated by the possible presence of third and fourth components with estimated masses of M3 = 2.20 M⊙ and M4 = 1.27 M⊙ in eccentric orbits of e3 = 0.66 and e4 = 0.52. Because the contribution of ℓ3 is very low compared to the estimated masses of two circumbinary objects, they can be inferred as very faint compact objects.

Keywords

Acknowledgement

This paper was based on observations obtained at the Sobaeksan Optical Astronomy Observatory(SOAO), which is operated by the Korea Astronomy and Space Science Institute (KASI). We would like to thank the SOAO staff for assistance during our observations. We also thanks C.-H. Kim for providing us the times of minimum light for V608 Cas. We have used the Simbad database maintained at CDS, Strasbourg, France.

References

  1. Applegate, J. H. 1992, A Mechanism for Orbital Period Modulation in Close Binaries, ApJ, 385, 621 https://doi.org/10.1086/170967
  2. Blattler, E., & Diethelm, R. 2001, V608 Cassiopeiae: CCD Light Curve and Elements of Variation, IBVS, 5151
  3. Bradstreet, D. H., & Guinan, E. F. 1994, Stellar Mergers and Acquisitions: The Formation and Evolution of W Ursae Majoris Binaries, in ASP Conf. Ser. 56, Interacting Binary Stars, ed. A. W. Shafter (San Francisco: ASP), 228
  4. Cook, S. P. 1999, An Improved Period for the Eclipsing binary V608 CAS, J. Amer. Assoc. Var. Star Obs., 27, 176
  5. D'Angelo, C., van Kerkwijk, M. H., & Rucinski, S. M. 2006, Contact Binaries with Additional Components. II. A Spectroscopic Search for Faint Tertiaries, AJ, 132, 650 https://doi.org/10.1086/505265
  6. Diethelm, R. 2009, Timings of Minima of Eclipsing Binaries, Inf. Bull. Variable Stars, No. 5871, 1
  7. Diethelm, R. 2010, Timings of Minima of Eclipsing Binaries, Inf. Bull. Variable Stars, No. 5920, 1
  8. Diethelm, R. 2011, Timings of Minima of Eclipsing Binaries, Inf. Bull. Variable Stars, No. 5960, 1
  9. Diethelm, R. 2012, Timings of Minima of Eclipsing Binaries, Inf. Bull. Variable Stars, No. 6011, 1
  10. Diethelm, R. 2013, Timings of minima of eclipsing binaries, Inf. Bull. Variable Stars, No. 6042, 1
  11. Eggleton, P. P. 2009, Towards multiple-star population synthesis, MNRAS, 399, 1471 https://doi.org/10.1111/j.1365-2966.2009.15372.x
  12. Eggleton, P. P., & Tokovinin, A. A. 2008, A catalogue of multiplicity among bright stellar systems, MNRAS, 389, 869 https://doi.org/10.1111/j.1365-2966.2008.13596.x
  13. Gaia Collaboration, Brown, A. G. A., Vallenari, A., et al. 2018, Gaia Data Release 2. Summary of the contents and survey properties, A&A, 616, A1 https://doi.org/10.1051/0004-6361/201833051
  14. Honkova, K., Jurysek, J., Lehky, M., et al. 2013, B.R.N.O. Contributions #38 Times of minima, Open Eur. J. Var. Stars, 160, 1
  15. Hubel, B. 1976, Neuer Veranderlicher S10797 Cassiopeiae., MitVS, 7, 184
  16. Hubscher, J. 2011, BAV-Results of Observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars, Inf. Bull. Variable Stars, No. 5984, 1
  17. Hubscher, J. 2017, BAV-Results of observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars, Inf. Bull. Variable Stars, No. 6196, 1
  18. Hubscher, J., & Walter, F. 2007, Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars, IBVS, 5761
  19. Hubscher, J., & Lehmann, P. B. 2012, BAV-Results of observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars, Inf. Bull. Variable Stars, No. 6026, 1
  20. Irwin, J. B. 1952, The Determination of a Light-Time Orbit., ApJ, 116, 211 https://doi.org/10.1086/145604
  21. Irwin, J. B. 1959, Standard light-time curves, AJ, 64, 149 https://doi.org/10.1086/107913
  22. Kang, Y. W., Oh, K.-D., Kim, C.-H., Hwang C., Kim, H.-I., & Lee, W.-B. 2002, Period variation and spot model for the W UMa type binary TY UMa, MNRAS, 331, 707 https://doi.org/10.1046/j.1365-8711.2002.05246.x
  23. Kim, C.-H., Jeong, J. H., Demircan, O., Muyesseroglu, Z., & Budding, E. 1997, The Period Changes of YY Eridani, AJ, 114, 2753 https://doi.org/10.1086/118684
  24. Kreiner, J. M., Kim, C.-H., & Nha, I.-S. 2001, An Atlas of O-C Diagrams of Eclipsing Binary Stars (Krakow: Wydawn. Nauk. Akad. Pedagogicznej)
  25. Kwee, K. K., & van Woerden, H. 1956, A method for computing accurately the epoch of minimum of an eclipsing variable, Bull. Astron. Inst. Netherlands, 12, 327
  26. Lanza, A. F., Rodono, M., & Rosner, R. 1998, Orbital period modulation and magnetic cycles in close binaries, MNRAS, 296, 893 https://doi.org/10.1046/j.1365-8711.1998.01446.x
  27. Lanza, A. F., & Rodono, M. 1999, Orbital period modulation and quadrupole moment changes in magnetically active close binaries, A&A, 349, 887
  28. Lee, J. W., Lee, C.-U., Kim, C.-H., & Kang, Y. W. 2006, A Photometric Study of the Contact Binary XZ Leonis, JKAS, 39, 41
  29. Lee, J. W., Park, J.-H., Hong, K., Kim, S.-L., & Lee, C.-U. 2014, Physical Nature and Timing Variations of the Eclipsing System V407 Pegasi, AJ, 147, 91 https://doi.org/10.1088/0004-6256/147/4/91
  30. Lenz, P., & Breger, M. 2005, Period04 User Guide, Commun. Asteroseismol., 146, 53 https://doi.org/10.1553/cia146s53
  31. Liu, L., Qian, S. B., He, J. J., et al. 2016, Photometric and period analysis of contact binary V608 Cassiopeiae, New A, 43, 1 https://doi.org/10.1016/j.newast.2015.07.005
  32. Lucy, L. B. 1967, Gravity-Darkening for Stars with Convective Envelopes, ZA, 65, 89
  33. Mardirossian F., Mezzetti M., Cester B., Giuricin G., & Russo G. 1980, Revised photometric elements of five possible sd-d systems., A&AS, 39, 235
  34. Mochnacki, S. W. 1984, Accurate integrations of the Roche model, ApJS, 55, 551 https://doi.org/10.1086/190967
  35. Nelson, R. H. 2010, CCD Minima for Selected Eclipsing Binaries in 2009, Inf. Bull. Variable Stars, No. 5929, 1
  36. Nelson, R. H. 2015, CCD Minima for Selected Eclipsing Binaries in 2014, Inf. Bull. Variable Stars, No. 6131, 1
  37. Nelson, R. H. 2016, CCD Minima for Selected Eclipsing Binaries in 2015, Inf. Bull. Variable Stars, No. 6164, 1
  38. Ogloza, W., Zola, S., Tremko, J., & Kreiner, J. M. 1998, The analysis of photometric light curves and the third body in the eclipsing binary system SW Lyn, A&A, 340, 81
  39. Pagel, L. 2018, BAV-Results of observations - Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars, Inf. Bull. Variable Stars, No. 6244, 1
  40. Panpiboon, P., Boontua, R., Thongcha, W., & Choawanklang, W. 2018, Light Curve Analysis and System Parameters of Contact Binary V608 Cassiopeiae, in J. Phys. Conf. Ser. 1144, 012166
  41. Pecaut, M. J., & Mamajek, E. E. 2013, Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-main-sequence Stars, ApJS, 208, 9 https://doi.org/10.1088/0067-0049/208/1/9
  42. Press, W., Flannery, B. P., Teukolsky, S. A., & Vetterling, W. T. 1992, Numerical Recipes (Cambridge : Cambridge Univ. Press), Chap. 15
  43. Pribulla, T., & Rucinski, S. M. 2006, Contact Binaries with Additional Components. I. The Extant Data, AJ, 131, 2986 https://doi.org/10.1086/503871
  44. Qian, S., & Yang, Y. 2005, Improved astrophysical parameters for the overcontact binary FG Hydrae, MNRAS, 356, 765 https://doi.org/10.1111/j.1365-2966.2004.08497.x
  45. Rappaport, S., Deck, K., Levine, A., Borkovits, T., Carter, J., El Mellah, I., Sanchis-Ojeda, R., & Kalomeni, B. 2013, Triple-star Candidates among the Kepler Binaries, ApJ, 768, 33 https://doi.org/10.1088/0004-637X/768/1/33
  46. Rucinski, S. M. 1969, The Proximity Effects in Close Binary Systems. II. The Bolometric Reflection Effect for Stars with Deep Convective Envelopes, AcA, 19, 245
  47. Rucinski, S. M., Pribulla, T., & van Kerkwijk, M. H. 2007, Contact Binaries with Additional Components. III. A Search Using Adaptive Optics, AJ, 134, 2353 https://doi.org/10.1086/523353
  48. Tian, X.-M., & Zhu, L.Y. 2019, V723 Persei: A short-period Algol-like near-contact binary, PASJ, 71, 66 https://doi.org/10.1093/pasj/psz044
  49. Tokovinin, A., Thomas, S., Sterzik, M., & Udry, S. 2006, Tertiary companions to close spectroscopic binaries, A&A, 450, 681 https://doi.org/10.1051/0004-6361:20054427
  50. van Hamme, W. 1993, New Limb-Darkening Coefficients for Modeling Binary Star Light Curves, AJ, 106, 2096 https://doi.org/10.1086/116788
  51. van Hamme, W., & Wilson, R. E. 2003, Stellar atmospheres in eclipsing binary models, in ASP Conf. Ser. 298, GAIA Spectroscopy, Science and Techology, ed. U. Munari (San Francisco, CA: ASP), 323
  52. Wilson, R. E., & Devinney, E. J. 1971, Realization of Accurate Close-Binary Light Curves: Application to MR Cygni, ApJ, 166, 605 https://doi.org/10.1086/150986