Astrophysics and Space Science

, Volume 110, Issue 2, pp 277–291

A model for symbiotic star Z Andromedae

  • B. F. Yudin
Article

Abstract

An analysis of the results of observations of the symbiotic star Z And has shown that no definite model can be derived at present on their basis. If the hot component is essentially an accreting white dwarf with a hydrogen-burning shell source, then the gas envelope must be optically thin for Lc-emission and itsTe must be in the neighborhood of 2.6×104K. And if the hot component is a Main-Sequence star with an accretion disk around it, then it is classified with red dwarfs. The electron temperature of the gas envelope must be 1.5×104K. The luminosity of the hot component at the minimum of its visual brightness is only a few times lower than its Eddington limit. Therefore, as the accretion rate goes up, the initial increase in its brightness (ΔU≲1m.5), unaccompanied by any perceptible changes in the spectrum of Z And, will be followed by disintegration of the regular disk and flare of the star in the visible range. In the same model, partial eclipses of the hot source must occur. They seem to be observable on the star's light curve in theU band. Substitution of a solar-type star for the first-named component in the binary ‘red dwarf + red giant’ system will lead to a significant decrease in the excitation of the combination spectrum.

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References

  1. Allen, D. A.: 1980,Monthly Notices Roy. Astron. Soc. 192, 521.Google Scholar
  2. Altamore, A., Baratta, G. B., and Viotti, R.: 1981,Inf. Bull. Var. Stars, No. 1636.Google Scholar
  3. Altamore, A., Baratta, G. B., Cassatella, A., Friedjung, M., Giangrande, A., Ricciardi, O., and Viotti, R.: 1981,Astrophys. J. 245, 630.Google Scholar
  4. Bath, G. T.: 1978,Monthly Notices Roy. Astron. Soc. 182, 35.Google Scholar
  5. Bath, G. T. and Pringle, J. E.: 1982,Monthly Notices Roy. Astron. Soc. 201, 345.Google Scholar
  6. Bath, G. T., Pringle, J. E., and Whelan, J. A. J.: 1980,Monthly Notices Roy. Astron. Soc. 190, 185.Google Scholar
  7. Belyakina, T. S.: 1965,Izv. Krymsk. Astrofiz. Obs. 33, 226.Google Scholar
  8. Belyakina, T. S.: 1970,Izv. Krymsk. Astrofiz. Obs. 41–42, 275.Google Scholar
  9. Beshenova, L. D. and Haritonov, A. V.: 1975,Proc. Astrofiz. Inst. Kazakh. S.R.R. 27.Google Scholar
  10. Blair, W. P., Stencel, R. E., Feibelman, W. A., and Michalitsanos, A. G.: 1983,Astrophys. J. Suppl. 53, 573.Google Scholar
  11. Boyarchuk, A. A.: 1966,Izv. Krymsk. Astrofiz. Obs. 35, 45.Google Scholar
  12. Boyarchuk, A. A.: 1967a,Izv. Krymsk. Astrofiz. Obs. 38, 155.Google Scholar
  13. Boyarchuk, A. A.: 1967b,Astron. Zh. 44, 1016.Google Scholar
  14. Boyarchuk, A. A.: 1970,Izv. Krymsk. Astrofiz. Obs. 41–42, 264.Google Scholar
  15. Carnochan, D. J. and Wilson, R.: 1983,Monthly Notices Roy. Astron. Soc. 202, 317.Google Scholar
  16. Echevarria, J.: 1983,Rev. Mex. Astron. Astrof. 8, 109.Google Scholar
  17. Iben, I., Jr: 1982,Astrophys. J. 259, 244.Google Scholar
  18. Ipatov, A. P. and Yudin, B. F.: 1984,Astron. Zh. in press.Google Scholar
  19. Kenyon, S. J. and Gallagher, J. S.: 1983,Astron. J. 88, 666.Google Scholar
  20. Lynden-Bell, D. and Pringle, J. E.: 1974,Monthly Notices Roy. Astron. Soc.,168, 603.Google Scholar
  21. Mattei, J. A.: 1978,J. Roy. Astron. Soc. Can. 72, 61.Google Scholar
  22. Meininger, L.: 1981,MVS 9, 67.Google Scholar
  23. Merrill, P. W.: 1948,Astrophys. J. 107, 317.Google Scholar
  24. Paczynski, B. and Rudak, B.: 1980,Astron. Astrophys. 82, 349.Google Scholar
  25. Swings, P. and Struve, O.: 1941,Astrophys. J. 93, 356.Google Scholar
  26. Taranova, O. G. and Yudin, B. F.: 1981a,Astron. Zh. 58, 1051.Google Scholar
  27. Taranova, O. G. and Yudin, B. F.: 1981b,Astron. Zh. 58, 1051.Google Scholar
  28. Taranova, O. G. and Yudin, B. F.: 1983,Astron. Tsirk., No. 1256.Google Scholar
  29. Taranova, O. G. and Yudin, B. F.: 1984,Astron. Tsirk., in press.Google Scholar
  30. Tsuji, F.: 1978,Astron. Astrophys. 62, 29.Google Scholar
  31. Tutukov, A. V. and Yungel'son, L. R.: 1976,Astrofizika 12, 521.Google Scholar
  32. Viotti, R., Giangrande, A., Riccardi, O., and Cassatella, A.: 1982, in M. Friedjung and R. Viotti (eds.), ‘The Nature of Symbiotic Stars’,IAU Colloq. 70, 125.Google Scholar
  33. Viotti, R., Riccardi, O., Ponz, D., Giangrande, A., Friedjung, M., Cassatella, A., Baratta, G. B., and Altamore, A.: 1982,Astron. Astrophys. 119, 285.Google Scholar
  34. Yudin, B. F.: 1981,Astron. Tsirk., No. 1160.Google Scholar

Copyright information

© D. Reidel Publishing Company 1985

Authors and Affiliations

  • B. F. Yudin
    • 1
  1. 1.Sternberg State Astronomical InstituteMoscowGermany

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