UBVJHKLM photometry of the symbiotic Mira V407 Cyg in 1998–2002 (original) (raw)

Abstract

New results of UBV JHKLM photometry of the symbiotic Mira V407 Cyg performed in 1998–2002 are reported. In 2002, these observations were supplemented with RI observations and a search for rapid variability in the V band. The hot component of V407 Cyg experienced a strong flare in 1998, which was the second in the history of photometric observations of this star; this flare is still continuing. During the flare, the spectral energy distribution of the hot component can be approximated by blackbody radiation with a temperature of ∼7200 K. At the maximum brightness, the bolometric flux from the hot component did not exceed 3% of the Mira's mean bolometric flux, while its bolometric luminosity was ∼400L⊙. Appreciable variations of the star's BV brightness \((\tilde0\mathop m\limits_. 7)\) on a timescale of several days have been observed. These variations are not correlated with variations of B-V. Flickering on a timescale of several minutes with an amplitude of \(\tilde0\mathop m\limits_. 2\) has been detected in the V band. The observations suggest that the hot component can be in three qualitatively different states. In a model with a rapidly rotating white dwarf, these states can be associated with (i) the quiescent state of the white dwarf (with a very low accretion rate), (ii) an ejection state, and (iii) an accretion state. The Mira pulsation period P is \( \approx 762\mathop d\limits_. 9\), with its infrared maximum occurring ∼0.15_P_ after the visual maximum. A “step” is observed on the ascending branch of the Mira infrared light curves. In 1998, the gradual increase of the mean K brightness of the Mira that had been observed since 1984 was interrupted by an unusually deep minimum, after which the mean level of the K brightness considerably decreased.

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References

  1. C. Hoffmeister, Veroff. Sternw. Sonnebrerg. 1, 295 (1949).
    ADS Google Scholar
  2. L. Meinunger, Mitt. Veranderl. Sterne. 87, 111 (1966).
    Google Scholar
  3. E. A. Kolotilov, Y. Munari, A. A. Popova, et al., Pis'ma Astron. Zh. 24, 526 (1998) [Astron. Lett. 24, 451 (1998)].
    ADS Google Scholar
  4. K. M. Merrill and C. G. Burwell, Astrophys. J. 112, 72 (1950).
    ADS Google Scholar
  5. G. Welin, Astron. Astrophys., Suppl. Ser. 9, 183 (1973).
    ADS Google Scholar
  6. V. F. Esipov, O. G. Taranova, and B. F. Yudin, Astrofizika 29, 285 (1986).
    Google Scholar
  7. U. Munari and T. Zwitter, Astron. Astrophys. 383, 188 (2002).
    Article ADS Google Scholar
  8. B. F. Yudin, Astron. Zh. 76, 198 (1999) [Astron. Rep. 43, 167 (1999)].
    Google Scholar
  9. A. U. Landolt, Publ. Astron. Soc. Pac. 87, 379 (1975).
    ADS Google Scholar
  10. G. W. Lockwood and R. F. Wing, Astrophys. J. 169, 63 (1971).
    Article ADS Google Scholar
  11. A. E. Nadzhip, A. M. Tatarnikova, V. I. Shenavrin, et al., Pis'ma Astron. Zh. 27, 376 (1999).
    Google Scholar
  12. P. A. Whitelock, New Astron. Rev. 43, 437 (1999).
    ADS Google Scholar
  13. U. Munari, R. Margoni, and R. Stagni, Mon. Not. R. Astron. Soc. 242, 653 (1990).
    ADS Google Scholar
  14. J. A. Mattei and J. Allen, J. R. Astron. Soc. Can. 73, 173 (1979).
    ADS Google Scholar
  15. L. A. Willson, P. Garnavich, and J. A. Mattei, Inform. Bull. Var. Stars, No. 1961 (1981).
  16. P. W. Merrill, Astrophys. J. 81, 312 (1935).
    ADS Google Scholar
  17. J. Mikolajewska, P. L. Selvelli, and M. Hack, Astron. Astrophys. 198, 150 (1988).
    ADS Google Scholar
  18. A. A. Boyarchuk, Astron. Zh. 44, 1016 (1967).
    ADS Google Scholar
  19. B. F. Yudin, Astrophys. Space Sci. 135, 143 (1987).
    Article ADS Google Scholar
  20. J. L. Sokoloski, L. Bildsten, and W. C. G. Ho, Mon. Not. R. Astron. Soc. 326, 553 (2001).
    Article ADS Google Scholar
  21. T. Tomov, D. Kolev, U. Munari, and A. Antov, Mon. Not. R. Astron. Soc. 278, 542 (1996).
    ADS Google Scholar
  22. M. Mikolajewski, T. Tomov, A. Dapergolas, and Y. Bellas-Veldis, in Cataclysmic Variables and Related Objects, Ed. by A. Evans and J. H. Wood (Kluwer, Dordrecht, 1996), p. 341.
    Google Scholar
  23. J. L. Sokoloski and L. Bildsten, Astrophys. J. 517, 919 (1999).
    Article ADS Google Scholar
  24. A. P. Ipatov, O. G. Taranova, and B. F. Yudin, Astron. Astrophys. 135, 325 (1984).
    ADS Google Scholar
  25. E. A. Olivier, P. Whitelock, and F. Marang, Mon. Not. R. Astron. Soc. 326, 490 (2001).
    Article ADS Google Scholar
  26. A. M. Tatarnikova, P. M. Marrese, U. Munari, et al., Pis'ma Astron. Zh. (in press).
  27. I. J. Sackmann and A. I. Boothroyd, Astrophys. J. 392, L71 (1992).
    Article ADS Google Scholar

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Authors and Affiliations

  1. Sternberg Astronomical Institute, Universitetskii pr. 13, Moscow, 119992, Russia
    E. A. Kolotilov, V. I. Shenavrin, S. Yu. Shugarov & B. F. Yudin

Authors

  1. E. A. Kolotilov
  2. V. I. Shenavrin
  3. S. Yu. Shugarov
  4. B. F. Yudin

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Translated from Astronomicheski\(\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\smile}$}}{l} \) Zhurnal, Vol. 80, No. 9, 2003, pp. 845–856.

Original Russian Text Copyright © 2003 by Kolotilov, Shenavrin, Shugarov, Yudin.

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Kolotilov, E.A., Shenavrin, V.I., Shugarov, S.Y. et al. UBVJHKLM photometry of the symbiotic Mira V407 Cyg in 1998–2002.Astron. Rep. 47, 777–788 (2003). https://doi.org/10.1134/1.1611218

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