Formation of Thorne–Żytkow objects in close binaries

  • Bumareyamu Hutilukejiang
  • Chunhua Zhu
  • Zhaojun Wang
  • Guoliang LüEmail author


Thorne–Żytkow objects (TŻOs), originally proposed by Thorne and Żytkow, may form as a result of unstable mass transfer in a massive X-ray binary after a neutron star (NS) is engulfed in the envelope of its companion star. Using a rapid binary evolution program and the Monte Carlo method, we simulated the formation of TŻOs in close binary stars. The Galactic birth rate of TŻOs is about \(1.5\times 10^{-4}~\hbox {yr}^{-1}\). Their progenitors may be composed of a NS and a main-sequence star, a star in the Hertzsprung gap or a core-helium burning, or a naked helium star. The birth rates of TŻOs via the above different progenitors are \(1.7\times 10^{-5}\), \(1.2\times 10^{-4}\), \(0.7\times 10^{-5}\), \(0.6\times 10^{-5}~\hbox {yr}^{-1}\), respectively. These progenitors may be massive X-ray binaries. We found that the observational properties of three massive X-ray binaries (SMC X-1, Cen X-3 and LMC X-4) in which the companions of NSs may fill their Roche robes were consistent with those of their progenitors.


Binary: close star: neutron X-ray: star. 



This work was supported by XinJiang Science Fund for Distinguished Young Scholars under No. 2014721015, the National Natural Science Foundation of China under Nos. 11473024, 11363005, 11763007 and 11503008.


  1. Bhattacharya D., van den Heuvel E. P. J. 1991, PhR, 203, 1ADSGoogle Scholar
  2. Biehle, G. T. 1991, ApJ, 380, 167ADSCrossRefGoogle Scholar
  3. Biehle, G. T. 1994, ApJ, 420, 364ADSCrossRefGoogle Scholar
  4. Cameron, A. G. W. 1955, ApJ, 121, 144ADSCrossRefGoogle Scholar
  5. Cannon, R. C., Eggleton, P. P., Zytkow, A. N., Podsiadlowski, P. 1992, ApJ, 386, 206ADSCrossRefGoogle Scholar
  6. de Kool, M. 1990, ApJ, 358, 189ADSCrossRefGoogle Scholar
  7. Eggleton, P. P., Fitchett, M. J., Tout, C. A. 1989, ApJ, 347, 998ADSCrossRefGoogle Scholar
  8. Goldberg, D., Mazeh, T. 1994, A&A, 282, 801ADSGoogle Scholar
  9. Han Z., Eggleton P. P., Podsiadlowski P., Tout C. A., Webbink R. F. 2001, in Podsiadlowski P., Rappaport S., King A. R., DAntona F., Burderi L., eds, Evolution of Binary and Multiple Star Systems, Astronomical Society of the Pacific Conference Series, Vol. 229, p 205Google Scholar
  10. Han, Z., Podsiadlowski, P., Eggleton, P. P. 1995, MNRAS, 272, 800ADSGoogle Scholar
  11. Han, Z., Podsiadlowski, P., Maxted, P. F. L., Marsh, T. R., Ivanova, N. 2002, MNRAS, 336, 449ADSCrossRefGoogle Scholar
  12. Harris, J., Zaritsky, D. 2004, AJ, 127, 1531ADSCrossRefGoogle Scholar
  13. Harris, J., Zaritsky, D. 2009, AJ, 138, 1243ADSCrossRefGoogle Scholar
  14. Hartman, J. W., Bhattacharya, D., Wijers, R., Verbunt, F. 1997, A&A, 322, 477ADSGoogle Scholar
  15. Hjellming, M. S., Webbink, R. F. 1987, ApJ, 318, 794ADSCrossRefGoogle Scholar
  16. Hobbs, G., Lorimer, D. R., Lyne, A. G., Kramer, M. 2005, MNRAS, 360, 974ADSCrossRefGoogle Scholar
  17. Hurley, J. R., Pols, O. R., Tout, C. A. 2000, MNRAS, 315, 543ADSCrossRefGoogle Scholar
  18. Hurley, J. R., Tout, C. A., Pols, O. R. 2002, MNRAS, 329, 897ADSCrossRefGoogle Scholar
  19. Iben, Jr., I., Livio, M. 1993, PASP, 105, 1373ADSCrossRefGoogle Scholar
  20. Katz, J. I. 1975, Nature, 253, 698ADSCrossRefGoogle Scholar
  21. Kiel, P. D., Hurley, J. R. 2006, MNRAS, 369, 1152ADSCrossRefGoogle Scholar
  22. Landau, L. 1938, Nature, 141, 333ADSCrossRefGoogle Scholar
  23. Leonard, P. J. T., Hills, J. G., Dewey, R. J. 1994, ApJL, 423, L19ADSCrossRefGoogle Scholar
  24. Levesque, E. M., Massey, P., Zytkow, A. N., B Morrell, N. 2014, MNRAS, 443, L94ADSCrossRefGoogle Scholar
  25. Liu, Q. Z., van Paradijs, J., van den Heuvel, E. P. J. 2006, A&A, 455, 1165ADSCrossRefGoogle Scholar
  26. Liu, X. W., Xu, R. X., van den Heuvel, E. P. J., et al. 2015, ApJ, 799, 233ADSCrossRefGoogle Scholar
  27. Maccarone, T. J., de Mink, S. E. 2016, MNRAS, 458, L1ADSCrossRefGoogle Scholar
  28. Mazeh, T., Goldberg, D., Duquennoy, A., Mayor, M. 1992, ApJ, 401, 265ADSCrossRefGoogle Scholar
  29. Miller, G. E., Scalo, J. M. 1979, ApJS, 41, 513ADSCrossRefGoogle Scholar
  30. Paczynski, B. 1976, in IAU Symposium, Vol. 73, Structure and Evolution of Close Binary Systems, ed. Eggleton, P., Mitton, S., Whelan, J. 75Google Scholar
  31. Pfahl, E., Rappaport, S., Podsiadlowski, P. 2002, ApJ, 573, 283ADSCrossRefGoogle Scholar
  32. Podsiadlowski, P., Cannon, R. C., Rees, M. J. 1995, MNRAS, 274, 485ADSCrossRefGoogle Scholar
  33. Ray, A., Kembhavi, A. K., Antia, H. M. 1987, A&A, 184, 164ADSGoogle Scholar
  34. Schneider, R., Valiante, R., Ventura, P., et al. 2014, MNRAS, 442, 1440ADSCrossRefGoogle Scholar
  35. Taam, R. E., Bodenheimer, P., Ostriker, J. P. 1978, ApJ, 222, 269ADSCrossRefGoogle Scholar
  36. Thorne, K. S., Zytkow, A. N. 1975, ApJL, 199, B L19ADSCrossRefGoogle Scholar
  37. Thorne, K. S., Zytkow, A. N. 1977, ApJ, 212, B 832ADSCrossRefGoogle Scholar
  38. Tout, C. A., Zytkow, A. N., Church, R. P., et al. 2014, MNRAS, 445, L36ADSCrossRefGoogle Scholar
  39. Wang, J. 2016, PhRvB, 94, 214502ADSGoogle Scholar
  40. Webbink, R. F. 1984, ApJ, 277, 355ADSCrossRefGoogle Scholar
  41. Worley, C. C., Irwin, M. J., Tout, C. A., et al. 2016, MNRAS, 459, L31ADSCrossRefGoogle Scholar
  42. Yisikandeer, A., Zhu, C., Wang, Z., Lü, G. 2016, JAA, 37, 22ADSGoogle Scholar
  43. Zhu, C., Lü, G., Wang, Z. 2015a, MNRAS, 454,1725ADSCrossRefGoogle Scholar
  44. Zhu, C., Lü, G., Wang, Z. 2015b, MNRAS, 451, 1561ADSCrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  • Bumareyamu Hutilukejiang
    • 1
  • Chunhua Zhu
    • 1
  • Zhaojun Wang
    • 1
  • Guoliang Lü
    • 1
    Email author
  1. 1.School of Physical Science and TechnologyXinjiang UniversityÜrümqiChina

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