Skip to main content
Log in

On timing and spectral characteristics of the X-ray pulsar 4U 0115+63: Evolution of the pulsation period and the cyclotron line energy

  • Published:
Astronomy Letters Aims and scope Submit manuscript

Abstract

An overview of the results of observations for the transient X-ray pulsar 4U 0115+63, amember of a binary system with a Be star, since its discovery to the present day (∼40 years) based on data from more than dozen observatories and instruments is presented. An overall light curve and the history of change in the spin frequency of the neutron star over the entire history of its observations, which also includes the results of recent measurements made by the INTEGRAL observatory during the 2004, 2008, and 2011 outbursts, are provided. The source’s energy spectra have also been constructed from the INTEGRAL data obtained during the 2011 outburst for a dynamic range of its luminosities 1037−7 × 1037 erg s−1. We show that apart from the fundamental harmonic of the cyclotron absorption line at energy∼11 keV, its four higher harmonics at energies ≃24, 35.6, 48.8, and 60.7 keV are detected in the spectrum. We have performed a detailed analysis of the source’s spectra in the 4–28 keV energy band based on all of the available RXTE archival data obtained during bright outbursts in 1995–2011. We have confirmed that modifying the source’s continuum model can lead to the disappearance of the observed anticorrelation between the energy of the fundamental harmonic of the cyclotron absorption line and the source’s luminosity. Thus, the question about the evolution of the cyclotron absorption line energy with the luminosity of the X-ray pulsar 4U 0115+63 remains open and a physically justified radiation model for X-ray pulsars is needed to answer it.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. M. M. Basko and R. A. Sunyaev, Mon. Not. R. Astron. Soc. 175, 395 (1976).

    ADS  Google Scholar 

  2. P. A. Becker and M. T. Wolff, Astrophys. J. 654, 435 (2007).

    Article  ADS  Google Scholar 

  3. L. Bildsten, D. Chakrabarty, J. Chiu, et al., Astrophys. J. Suppl. Ser. 113, 367 (1997).

    Article  ADS  Google Scholar 

  4. H. V. Bradt, R. E. Rothschild, and J. H. Swank, Astron. Astrophys. Suppl. Ser. 97, 355 (1993).

    ADS  Google Scholar 

  5. D. J. Burnard, J. Arons, and R. I. Klein, Astrophys. J. 367, 575 (1991).

    Article  ADS  Google Scholar 

  6. S. Campana, F. Gastaldello, L. Stella, et al., Astrophys. J. 561, 924 (2001).

    Article  ADS  Google Scholar 

  7. L. Cominsky, F. Li, H. Bradt, et al., IAU Circ. 3163, 1 (1978).

    ADS  Google Scholar 

  8. L. Cominsky, M. Roberts, and M. H. Finger, Am. Inst. Phys. Conf. Ser. 304, 294 (1994).

    ADS  Google Scholar 

  9. C. Ferrigno, P. A. Becker, A. Segreto, et al., Astron. Astrophys. 498, 825 (2009).

    Article  ADS  Google Scholar 

  10. C. Ferrigno, M. Falanga, E. Bozzo, et al., Astron. Astrophys. 532, A76 (2011).

    Article  ADS  Google Scholar 

  11. M. H. Finger, M. Scott, K. Hagedon, et al., IAU Circ. 6266, 2 (1995).

    ADS  Google Scholar 

  12. W. Forman, C. Jones, L. Cominsky, et al., Astrophys. J. Suppl. Ser. 38, 357 (1978).

    Article  ADS  Google Scholar 

  13. P. Ghosh and F. K. Lamb, Astrophys. J. 234, 296 (1979).

    Article  ADS  Google Scholar 

  14. R. Giacconi, S. Murray, H. Gursky, et al., Astrophys. J. 178, 281 (1972).

    Article  ADS  Google Scholar 

  15. M. Gilfanov, R. Sunyaev, E. Churazov, et al., Astron. Lett. 17, 108 (1991).

    Google Scholar 

  16. W. A. Heindl, W. Coburn, D. E. Gruber, et al., Astrophys. J. Lett. 521, L49 (1999).

    Article  ADS  Google Scholar 

  17. J. B. Hutchings and D. Crampton, Astrophys. J. 247, 222 (1981).

    Article  ADS  Google Scholar 

  18. A. F. Illarionov and R. A. Sunyaev, Astron. Astrophys. 39, 185 (1975).

    ADS  Google Scholar 

  19. M. Johns, A. Koski, C. Canizares, et al., IAU Circ. 3171, 1 (1978).

    ADS  Google Scholar 

  20. M. Johnston, H. Bradt, R. Doxsey, et al., Astrophys. J. Lett. 223, L71 (1978).

    Article  ADS  Google Scholar 

  21. R. L. Kelley, M. J. Brodheim, L. Cominsky, et al., Astrophys. J. 251, 630 (1981).

    Article  ADS  Google Scholar 

  22. P. N. Kholopov, N. N. Samus’, N. P. Kukarkina, et al., Inform. Bull. Var. Stars 2042, 1 (1981).

    ADS  Google Scholar 

  23. D. Klochkov, A. Santangelo, R. Staubert, et al., Astron. Astrophys. 532, A126 (2011).

    Article  ADS  Google Scholar 

  24. G. A. Kriss, L. R. Cominsky, R. A. Remillard, et al., Astrophys. J. 266, 806 (1983).

    Article  ADS  Google Scholar 

  25. R. Krivonos, M. Revnivtsev, S. Tsygankov, et al., Astron. Astrophys. 519, A107 (2010).

    Article  ADS  Google Scholar 

  26. D. A. Leahy, R. F. Elsner, and M. C. Weisskopf, Astrophys. J. 272, 256 (1983).

    Article  ADS  Google Scholar 

  27. D. A. Leahy, Mon. Not. R. Astron. Soc. 251, 203 (1991).

    ADS  Google Scholar 

  28. J. Li, W. Wang, and Y. Zhao, Mon. Not. R. Astron. Soc. 423, 2854 (2012).

    Article  ADS  Google Scholar 

  29. A. A. Lutovinov, S. A. Grebenev, R. A. Syunyaev, and M. N. Pavlinskii, Astron. Lett. 20, 538 (1994).

    ADS  Google Scholar 

  30. A. A. Lutovinov, S. A. Grebenev, and R. A. Sunyaev, Astron. Lett. 26, 1 (2000).

    Article  ADS  Google Scholar 

  31. A. Lutovinov, C. Budtz-Jorgensen, M. Turler, et al., Astron. Telegram 326, 1 (2004).

    ADS  Google Scholar 

  32. A. A. Lutovinov and S. S. Tsygankov, Astron. Lett. 35, 433 (2009).

    Article  ADS  Google Scholar 

  33. A. Lutovinov, S. Tsygankov, and M. Chernyakova, Mon. Not. R. Astron. Soc. 423, 1978 (2012).

    Article  ADS  Google Scholar 

  34. F. Makino (GINGATeam), IAU Circ. 4967, 1 (1990).

    ADS  Google Scholar 

  35. H. Mendelson and T. Mazeh, IAU Circ. 4350, 2 (1987).

    ADS  Google Scholar 

  36. H. Mendelson and T. Mazeh, Mon. Not. R. Astron. Soc. 250, 373 (1991).

    ADS  Google Scholar 

  37. T. Mihara, K. Makishima, and F. Nagase, Astrophys. J. 610, 390 (2004).

    Article  ADS  Google Scholar 

  38. N. Mowlavi, I. Kreykenbohm, S. E. Shaw, et al., Astron. Astrophys. 451, 187 (2006).

    Article  ADS  Google Scholar 

  39. S. Muller, C. Ferrigno, M. Kuhnel, et al., Astron. Astrophys. 551, A6 (2013).

    Article  ADS  Google Scholar 

  40. J. Poutanen, A. Mushtukov, V. Suleimanov, et al., ApJ, submitted, arXiv:1304.2633

  41. M. Nakajima, T. Mihara, K. Makishima, et al., Astrophys. J. 646, 1125 (2006).

    Article  ADS  Google Scholar 

  42. M. Nakajima, T. Mihara, and K. Makishima, Astrophys. J. 710, 1755 (2010).

    Article  ADS  Google Scholar 

  43. I. Negueruela and A. T. Okazaki, Astron. Astrophys. 369, 108 (2001).

    Article  ADS  Google Scholar 

  44. A. T. Okazaki and I. Negueruela, Astron. Astrophys. 377, 161 (2001).

    Article  ADS  Google Scholar 

  45. H. Raichur and B. Paul, Mon. Not. R. Astron. Soc. 406, 2663 (2010).

    Article  ADS  Google Scholar 

  46. S. Rappaport, G. W. Clark, L. Cominsky, et al., Astrophys. J. Lett. 224, L1 (1978).

    Article  ADS  Google Scholar 

  47. P. Reig, Mon. Not. R. Astron. Soc. 377, 867 (2007).

    Article  ADS  Google Scholar 

  48. P. Reig, Astrophys. Space Sci. 332, 1 (2011).

    Article  ADS  Google Scholar 

  49. M. J. Ricketts, R. Hall, C. G. Page, et al., Space Sci. Rev. 30, 399 (1981).

    Article  ADS  Google Scholar 

  50. L. A. Rose, F. E. Marshall, S. S. Holt, et al., Astrophys. J. 231, 919 (1979).

    Article  ADS  Google Scholar 

  51. A. Santangelo, A. Segreto, S. Giarrusso, et al., Astrophys. J. Lett. 523, L85 (1999).

    Article  ADS  Google Scholar 

  52. M. Sasaki, D. Müller, U. Kraus, et al., Astron. Astrophys. 540, A35 (2012).

    Article  ADS  Google Scholar 

  53. S. Sazonov and R. Sunyaev, IAU Circ. 6272, 2 (1995).

    ADS  Google Scholar 

  54. M. Scott, M. H. Finger, R. B. Wilson, et al., IAUCirc. 6450, 1 (1996).

    ADS  Google Scholar 

  55. N. I. Shakura, Sov. Astron. Lett. 1, 223 (1975).

    ADS  Google Scholar 

  56. A. Slettebak, Proc. Astron. Soc. Pacif. 100, 770 (1988).

    Article  ADS  Google Scholar 

  57. K. Tamura, H. Tsunemi, S. Kitamoto, et al., Astrophys. J. 389, 676 (1992).

    Article  ADS  Google Scholar 

  58. H. Tsunemi and S. Kitamoto, Astrophys. J. Lett. 334, L21 (1988).

    Article  ADS  Google Scholar 

  59. S. S. Tsygankov, A. A. Lutovinov, E. M. Churazov, and R. A. Sunyaev, Mon. Not. R. Astron. Soc. 371, 19 (2006).

    Article  ADS  Google Scholar 

  60. S. S. Tsygankov, A. A. Lutovinov, E. M. Churazov, and R. A. Sunyaev, Astron. Lett. 33, 368 (2007).

    Article  ADS  Google Scholar 

  61. S. S. Tsygankov, A. A. Lutovinov, and A. V. Serber, Mon. Not. R. Astron. Soc. 401, 1628 (2010).

    Article  ADS  Google Scholar 

  62. W. A. Wheaton, J. P. Doty, F. A. Primini, et al., Nature 282, 240 (1979).

    Article  ADS  Google Scholar 

  63. N. E. White, J. H. Swank, and S. S. Holt, Astrophys. J. 270, 711 (1983).

    Article  ADS  Google Scholar 

  64. L. Whitlock, D. Roussel-Dupre, and W. Priedhorsky, Astrophys. J. 338, 381 (1989).

    Article  ADS  Google Scholar 

  65. R. B. Wilson, M. H. Finger, and D. M. Scott, IAU Circ. 5999, 2 (1994).

    ADS  Google Scholar 

  66. R. B. Wilson, B. A. Harmon, and M. H. Finger, IAU Circ. 7116, 1 (1999).

    ADS  Google Scholar 

  67. C. Winkler, T. J.-L. Courvoisier, G. Di Cocco, et al., Astron. Astrophys. 411, L1 (2003).

    Article  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to P. A. Boldin.

Additional information

Original Russian Text © P.A. Boldin, S.S. Tsygankov, A.A. Lutovinov, 2013, published in Pis’ma v Astronomicheskiĭ Zhurnal, 2013, Vol. 39, No. 6, pp. 423–437.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Boldin, P.A., Tsygankov, S.S. & Lutovinov, A.A. On timing and spectral characteristics of the X-ray pulsar 4U 0115+63: Evolution of the pulsation period and the cyclotron line energy. Astron. Lett. 39, 375–388 (2013). https://doi.org/10.1134/S1063773713060029

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S1063773713060029

Keywords

Navigation