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The Nature and Evolutionary Status of GRO J1744–28

Published online by Cambridge University Press:  12 April 2016

P. C. Joss  and
S. Rappaport
P. C. Joss
Affiliation:
Massachusetts Institute of Technology
S. Rappaport
Affiliation:
Massachusetts Institute of Technology

Abstract

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GRO J1744–28 is the first known X-ray source to display both bursts and periodic pulsations. This source may thus provide crucial clues that will lead to an understanding of the differences in the nature of the X-ray variability among accreting neutron stars. We deduce that the magnetic field of the neutron star is relatively weak (~ 8 × 1010 G) but, nevertheless, sufficiently strong to funnel the accretion flow onto the magnetic polar caps and suppress the thermonuclear flashes that would otherwise give rise to type I X-ray bursts. We also present a series of interrelated arguments which demonstrate that the observed bursts are of type II and probably result from an instability associated with the interaction of the neutron-star magnetic field with the inner edge of the accretion disk. From these results, we infer that X-ray pulsars, GRO J1744–28, the Rapid Burster, and the type I X-ray bursters may form a sequence of possible behaviors among accreting neutron stars, with the strength of the magnetic field serving as the crucial parameter that determines the mode of X-ray variability. The companion star in the GRO J1744–28 binary system is probably a very low-mass (~ 0.2 M⊙) giant that is in the final stages of losing its hydrogen-rich envelope. We have carried out binary evolution calculations which show that (1) if the mass of the giant was ~ 1 M⊙ when mass transfer onto the neutron star commenced, then the orbital period and the core mass of the giant have increased from ~ 1 to ~ 11.8 days and from ~ 0.15 to ~ 0.21 M⊙, respectively, during the mass-transfer epoch, which has lasted for ~ 8 × 108 yr, (2) the present long-term average X-ray luminosity is ~ 4 × 1036 ergs s−1, which is at least two orders of magnitude lower than the luminosity at the peak of the transient outburst, and (3) the predicted long-term equilibrium rotation rate of the neutron star is remarkably close to the observed pulse rate. The transient nature of GRO J1744–28 may well be related to the final stages of dissipation of the envelope of the giant companion.

Type
Part 7. Local and Global Instabilities and Disk Perturbations
Information
International Astronomical Union Colloquium , Volume 163: Accretion Phenomena and Related Outflows , 1997 , pp. 289 - 299
Copyright
Copyright © Astronomical Society of the Pacific 1997

References

Alpar, M.A., & Shaham, J. 1985, Nature, 316, 239 CrossRefGoogle Scholar
Ayasli, S., & Joss, P.C. 1982, ApJ, 256, 637 Google Scholar
Bildsten, L., & Brown, E.F. 1996, ApJ, in pressGoogle Scholar
Böhm-Vitense, E. 1958, ZAp, 46, 108 Google Scholar
Briggs, M.S. et al. 1996, IAU Circ., No. 6290 Google Scholar
Cannizzo, J.K. 1993, ApJ, 419, 318 Google Scholar
Cheng, F.H., & Lin, D.N.C. 1992, ApJ, 389, 714 CrossRefGoogle Scholar
Cox, J.P., & Giuli, R.T. 1968, Principles of Stellar Structure and Evolution, Vol. 1 (New York: Gordon & Breach)Google Scholar
Daumerie, P., Kalogera, V., Lamb, F.K., & Psaltis, D. 1996, Nature, 382, 141 CrossRefGoogle Scholar
Finger, M.H., Koh, D.T., Nelson, R.W., Prince, T.A., Vaughan, B.A., & Wilson, R.B. 1996a, IAU Circ., No. 6285 Google Scholar
Finger, M.H., Wilson, R.B., & van Paradijs, J. 1996b, IAU Circ., No. 6286 Google Scholar
Fishman, G.J. et al. 1995, IAU Circ., No. 6272 Google Scholar
Fishman, G.J. et al. 1996, IAU Circ., No. 6290 Google Scholar
Ghosh, P., & Lamb, F.K. 1979, ApJ, 234, 296 CrossRefGoogle Scholar
Giles, B., & Strohmayer, T. 1996, IAU Circ., No. 6338 Google Scholar
Härm, R., & Schwarzschild, S. 1975, 200, 324 Google Scholar
Joss, P.C. 1977, Nature, 230, 310 Google Scholar
Joss, P.C. 1978, ApJ, 238, L123 CrossRefGoogle Scholar
Joss, P.C., & Li, F.K. 1980, ApJ, 238, 287 Google Scholar
Joss, P.C., & Rappaport, S. 1976, Nature, 264, 219 Google Scholar
Joss, P.C., & Rappaport, S. 1983, Nature, 304, 419 Google Scholar
Joss, P.C., & Rappaport, S.A. 1984, ARA&A, 22, 537 Google Scholar
Kopal, Z. 1959, Close Binary Systems (London: Chapman & Hall).Google Scholar
Joss, P.C., Rappaport, S., & Lewis, W. 1987, ApJ, 319, 180 CrossRefGoogle Scholar
Kommers, J., & Fox, D. 1996, unpublishedGoogle Scholar
Kouveliotou, C. 1996, IAU Circ., No. 6369 Google Scholar
Kouveliotou, C. et al. 1996a, IAU Circ., No. 6286 Google Scholar
Kouveliotou, C. et al. 1996b, Nature, 379, 799 CrossRefGoogle Scholar
Lamb, D.Q., Miller, M.C., & Taam, R.E. 1996, preprintGoogle Scholar
Lewin, W.H.G. et al. 1976, ApJ, 207, L95 CrossRefGoogle Scholar
Lewin, W.H.G., & Joss, P.C. 1981, Space Sci.Rev., 28, 3 CrossRefGoogle Scholar
Lewin, W.H.G., Rutledge, R.E., Kommers, J.M., van Paradijs, J., & Kouveliotou, C. 1996, ApJ, 462, L39 Google Scholar
Lewin, W.H.G., van Paradijs, J., & Taam, R.E. 1993, Space Sci.Rev., 62, 223 Google Scholar
Morgan, E. 1996, private communicationGoogle Scholar
Paciesas, W.S., Harmon, B.A., Fishman, G.J., Zhang, S.N., & Robinson, C.R. 1996, IAU Circ., No. 6284 Google Scholar
Paczyński, B. 1983, Nature, 304, 421 Google Scholar
Rappaport, S., & Joss, P.C. 1977, Nature, 266, 683 Google Scholar
Rappaport, S., Podsiadlowski, Ph., Joss, P.C., Di Stefano, R., & Han, Z. 1995, MNRAS, 273, 731 CrossRefGoogle Scholar
Rappaport, S., Verbunt, F., & Joss, P.C. 1983, ApJ, 275, 713 CrossRefGoogle Scholar
Ruderman, M.A., & Sutherland, P.G. 1975, ApJ, 196, 51 Google Scholar
Savonije, G.J. 1983, Nature, 304, 422 Google Scholar
Strickman, M.S. et al. 1996, preprintGoogle Scholar
Stumer, S.J., & Dermer, C.D. 1996, ApJ, 465, L31 Google Scholar
Swank, J. 1996, IAU Circ., No. 6291 Google Scholar
Tawara, Y., Hayakawa, S., Kunieda, H., Makino, F., & Nagase, F. 1982, Nature, 299, 38 Google Scholar
Verbunt, F., & Zwaan, C. 1981, A&A, 100, L7 Google Scholar
Webbink, R.F., Rappaport, S., & Savonije, G.J. 1983, ApJ, 270, 678 Google Scholar
Zhang, W. et al. 1996, IAU Circ., No. 6300 Google Scholar