Abstract
The present knowledge of the structure of low-mass X-ray binary systems is reviewed. We examine the orbital period distribution of these sources and discuss how the orbital periods are measured. There is substantial observational evidence that the accretion disks in low-mass X-ray binaries are thick and structured. In a number of highly inclined systems, the compact X-ray emitting star is hidden from direct view by the disk and X-radiation is observed from these only because photons are scattered into the line of sight by material above and below the disk plane. In such systems the X-ray emission can appear extended with respect to the companion star, which can lead to partial X-ray eclipses. There are substantial variations in the thickness of the disk rim with azimuth. These give rise to the phenomenon of irregular dips in the X-ray flux which recur with the orbital period, or to an overall binary modulation of the X-ray flux if the source is “extended”. The X-ray spectra of low-mass X-ray binaries can be used to probe the innermost emission regions surrounding the compact star. The spectra of the bright “Sco X-1” variables can be fitted with two components which are provisionally identified as originating in the inner disk and the boundary layer between the disk and the neutron star respectively. The characteristic energy dependent flaring of the “Sco X-1” sub-class may be a geometric effect triggered by an increase in the thickness of the inner disk or boundary layer. The X-ray spectra of the lower luminosity systems, including the bursters, are less complex, and in many cases can be represented by a single power law with, in some sources, a high energy cut-off. Iron line emission is a characteristic of most low-mass X-ray binaries, irrespective of luminosity.
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References
Acton, L.W., Catura, R.C., Culhane, J.L., and Fisher, P.C., 1970, Ap.J. 161, L175.
Ayasli, S. and Joss, P., 1982, Ap.J. 256, 637.
Begelman, M.C., McKee, C.F., and Shields, G.A., 1983, Ap.J. 271, 70.
Begelman, M.C. and McKee, C.F., 1983, Ap.J. 271, 89.
Canizares et al., 1975, Ap.J. 197, 457.
Chodil et al. 1968, Ap.J., 154, 645.
Cominsky, L. and Wood, K. 1984, Ap J, 283, 765.
Cordova, F.A., and Mason, K.O. 1983 in Accretion driven stellar X-ray sources ed. W.H.G. Lewin and E.P.J. van den Heuvel, Cambridge University Press, Cambridge, England, pg. 147.
Cowley, A.P. and Crampton, D., 1975, Ap.J. 201, L65.
Cowley, A.P., Crampton, D. and Hutchings, J.B. 1979, Ap.J. 231, 539.
Courvoisier, T., Parmar A.N. and Peacock, A.P., 1984, I.A.U.C. No 3952.
Eardley, D.M., Lightman, A.P., Payne, D.G. and Shapiro, S.L., 1978 Ap.J., 224, 53.
Fabian, A.C., Guilbert P. and Ross, R. 1982 M.N.R.A.S. 199, 1045.
Gottlieb, E.W., Wright, E.L. and Liller, W. 1975, Ap.J. 195, L33.
Gottwald, M.G., Barr, P. and White, N.E.,1985, in preperation.
Holt, S.S., Boldt, E.A. and Serlemitsos, P.J. 1969, Ap.J. 154, L137.
Ilovaisky, S.A., Chevalier, C., White, N.E., Mason, K.O., Sanford, P.W., Devaille, J., and Schnopper, H.W. 1980, M.N.R.A.S. 191, 81.
Joss, P.C. and Rappaport, S.A. 1979, Astr. Ap. 71, 217.
Kylafis, N.D. and Lairtb, D.Q. 1978 Ap.J. 228, L105.
Lamb, P. and Sanford, P. W., 1978, M.N.R.A.S. 188, 555.
Laros, J.G. and Singer, S. 1976, Ap.J. 205, 550
Lewin, W.H.G. and Joss, P.C. 1983 in Accretion driven stellar X-ray sources ed. W.H.G. Lewin and E.P.J. van den Heuvel, Cambridge University Press, Cambridge, England, pg. 41.
Long, K.S. and Kestenbaum, H.L. 1978, Ap.J. 226, 276.
Mason, K.O., and Cordova, F.A. 1982a Ap.J. 255, 603.
Mason, K.O., and Cordova, F.A. 1982b Ap.J. 262, 253.
Mason, K.O., Cordova, F.A., Corbet, R.H.D., and Branduardi-Raymont, G. 1985 (these proceedings).
Mason, K.O., Charles, P.A., White, N.B., Culhane, J.L., Sanford, P.W., and Strong, K.T. 1976 M.N.R.A.S. 177, 513.
Mason, K.O., Middleditch, J., Nelson, J.E., and White, N.E. 1980, Nature 287, 516.
Mason, K.O., Middleditch, J., Nelson, J.E., White, N.E., Seitzer, P., Tuohy, I. R., and Hunt, L.K. 1980, Ap.J. 242, L109.
Mason, K.O., Murdin, P.G., Tuohy, I.R., Seitzer, P., and Branduardi-Raymont, G. 1982, M.N.R.A.S. 200, 793.
Matsuoka, M. et al. 1985, P.A.S.J. (in press).
McClintock, J.E., London, R.A., Bond, H.E. and Grauer, A.D. 1982, Ap.J. 258, 245.
McClintock, J.E., Remillard, R.A. and Margon, B. 1981, Ap.J. 243, 900.
Meyer, F. and Meyer-Hoffmeister, E. 1984, Astr. Ap. (in press).
Middleditch, J., Mason, K.O., Nelson, J.E. and White, N.E. 1981, Ap.J. 244, 1001.
Milgrom, M. 1978, Astr. Ap. 208, 191.
Motch, C. et al. 1984, I.A.U.C. No 3951.
Neugebauer, G., Oke, J.B., Becklin, E. and Garmire, G. 1969, Ap.J. 155, 1.
Parmar, A.N., Pietsch, W., McKechnie, S., White, N.E., Trumper, J., Voges, W., and Barr, P. 1985, Nature (in press).
Parsignault et al. 1972, Nature (Phys Sci) 239, 123.
Pakull, M. 1985; these proceedings.
Pedersen, H., van Paradijs, J. and Lewin, W.H.G. 1981, Nature 294, 725.
Petro, L., Bradt, H., Kelley, R., Horne, K., Gomer, R. 1981, Ap.J. 251, L7.
Pringle, J.E. and Rees, M.J. 1972, Astr. Ap. 21, 1.
Sanford, P.W. and Hawkins F.J. 1972, Nature (Phys Sci), 239, 135
Shakura, N.I. and Sunyaev, R.A. 1973, Astr. Ap 24, 337.
Stella, L., Kahn S., and Grindlay, J.E. 1984, Ap.J., 282, 713.
Sztajno, M. and Frank, J. 1984, Astr. Ap., 138, L15.
Tanaka, Y. 1985 (these proceedings).
Tananbaum, H., Gursky, H., Kellogg, E., Levison, R., Schreier, E., Giacconi, R. 1972, Ap.J. 174, L143.
Thorstensen, J.R., Charles, P.A., Bowyer S., Briel, U.G., Doxsey, R.E., Griffiths, R.E., Schwartz, D. 1979, Ap.J. 233, L57.
Turner, M.J.L and Breedon, L.M. 1984, M.N.R.A.S. 208, 29P.
Turner, M.J.L. et al. 1985, (these proceedings),
van Paradijs, J. 1983, in Accretion driven stellar X-ray sources ed. W.H.G. Lewin and E.P.J. van den Heuvel, Cambridge University Press, Cambridge, England, pg. 189.
Verbunt, F., van Paradijs and Elson, R. 1984, M.N.R.A.S. 210, 899.
Walter, F.M., Bowyer, S., Mason, K.O., Clarke, J.T., Henry, J.P., Halpern, J. and Grindlay, J.E. 1982, Ap.J. 253, L67.
Watson, M.G. et al. 1985 (these proceedings).
White, N.E., Becker, R.H., Boldt, E.A., Holt, S.S., Serlemitsos, P.J. and Swank, J.H. 1981, Ap.J. 247, 994.
White, N.E., Charles, P.A. and Thorstensen, J. 1980, M.N.R.A.S. 193, 731.
White, N.E. and Holt, S.S. 1982, Ap.J. 257, 318.
White, N.E. and Marshall, F.E. 1984, Ap.J. 281, 354.
White, N.E., Mason, K.O., Sanford, P.W., Ilovaisky, S.A. and Chevalier C. 1976, M.N.R.A.S. 176, 91.
White, N.E., Mason, K.O., Sanford, P.W., Johnson, H.M. and Catura, R.C. 1978, Ap.J. 220, 600.
White, N.E., Parmar, A.N., Sztajno, M., Zimmermann, H.U., Mason, K.O. and Kahn, S.H. 1984, Ap.J., 283, L9.
White, N.E., Peacock, A.P. and Taylor, B.G. 1985 Ap. J. (submitted).
White, N.E. and Swank, J.H. 1982, Ap.J. 253, L61.
White, N.E. et al., 1985 (in preparation).
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White, N.E., Mason, K.O. The structure of low-mass X-ray binaries. Space Sci Rev 40, 167–194 (1985). https://doi.org/10.1007/BF00212883
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DOI: https://doi.org/10.1007/BF00212883