Accretion Disk Electrodynamics

  • M. Kuperus
Part of the NATO ASI Series book series (NSSB, volume 156)


A plasma cloud orbiting around a compact object of mass M with the Kepler velocity vϕ = (GM/ r)1/2 at a distance r from the center of the object has an angular momentum I = mΩr2 , where m is the mass of the cloud and Ω = vϕ/r is tne angular velocity. The inner parts of the cloud have a larger angular velocity then the outer parts do thus creating a shear. The result of this differential rotation is twofold. First the cloud is stretched in the azimuthal direction until a ring is formed. Secondly because of the shear the cloud diffuses in the radial direction transporting mass inward as well as outward. The innermost parts of the ring are slowed down due to the viscous drag caused by the slower moving outer parts while the outer parts are accelerated due to the viscous drag of the faster moving inner parts. Consequently the inner parts start drifting inwards and the outer parts start drifting outwards. Since the angular momentum is proportional to r2 the outflowing parts of the plasma cloud transport more angular momentum outward then the inward moving parts transport inward. Due to the viscous processes inside the disk the outward transport of angular momentum is achieved thus facilitating the process of accretion.


Angular Momentum Neutron Star Accretion Disk Differential Rotation Compact Object 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Shakura, N.I., and Sunyaev, R.A., 1973, Astron. Astrophys. 24, 337ADSGoogle Scholar
  2. 2.
    Frank, J., King A.R., and Raine, D.J., 1985, “Accretion power in Astrophysics”, Cambridge Univ. Press, CambridgeGoogle Scholar
  3. 3.
    Lightman, A.P., 1974, Astrophys. J. 194, 419Google Scholar
  4. 4.
    Lightman, A.P., and Eardley, D.M., 1974, Astrophys. J. 187, L1ADSCrossRefGoogle Scholar
  5. 5.
    Shapiro, S.L., Lightman, A.P. and Eardley, D.M., 1976, Astrophys. J. 204, 187Google Scholar
  6. 6.
    Zeld’dovich, Ya.B. Ruzmaikin A.A., and Sokoloff,D.D., 1983, “Magnetic Fields in Astrophysics”, Gordon & Breach Publ.Google Scholar
  7. 7.
    Pudritz, R.E., 1981a, Mon. Not. Roy. Astron. Soc. 195, 881Google Scholar
  8. 8.
    Pudritz, R.E., 1981b, Mon. Not. Roy. Astron. Soc. 195, 897Google Scholar
  9. 9.
    Meyer, F., and Meyer-Hofmeister, E., 1982, Astron. & Astrophys. 106,34ADSGoogle Scholar
  10. 10.
    Burm, H.M.G., 1985, Astron. & Astrophys. 132, 143Google Scholar
  11. 11.
    Pudritz, R.E., and Fahlmann, G.G., 1982, Mon. Not. Roy. Astron. Soc. 198, 689ADSGoogle Scholar
  12. 12.
    Eardley, D.M., and Lightman, A.P., 1975, Astrophys. J. 200, 187Google Scholar
  13. 13.
    Coroniti, F.V., 1981, Astrophys. J. 244, 587Google Scholar
  14. 14.
    Coroniti, F.V., 1983, IAU symp. 107, 453, eds. M.R. Kundu and G.D. HolmanGoogle Scholar
  15. 15.
    Liang, E.P.T., and Price, R.H., 1977, Astrophys. J. 218, 247ADSCrossRefGoogle Scholar
  16. 16.
    Galeev, A.A., Rosner, R., and Vaiana, G.S., 1979, Astrophys. J. 229,318Google Scholar
  17. 17.
    Ionson, J.A., and Kuperus, M., 1984, Astrophys. J. 284, 389ADSCrossRefGoogle Scholar
  18. 18.
    Kuperus, M. and Ionson, J.A., 1985, Astron. & Astrophys. 148, 309ADSGoogle Scholar
  19. 19.
    Ionson, J.A., 1982, Astrophys. J. 254, 318Google Scholar
  20. 20.
    Ionson, J.A., 1984, Astrophys. J. 276, 357ADSCrossRefGoogle Scholar
  21. 21.
    Liang, E.P.T., 1980, Nature 283, 642Google Scholar
  22. 22.
    Gosh, P., and Lamb, F.K., 1978, Astrophys. J. 223, L83ADSCrossRefGoogle Scholar
  23. 23.
    Gosh, P. and Lamb, F.K., 1979a, Astrophys. J. 232, 259ADSCrossRefGoogle Scholar
  24. 24.
    Gosh, P. and Lamb, F.K., 1979b, Astrophys. J. 234, 296Google Scholar
  25. 25.
    Kaburaki, 1986, Mon. Not. Roy. Astron. Soc. 220, 321Google Scholar
  26. 26.
    Dewey, R.J., Maguire, C.M., Rawley, L.A., Stokes, G.H., and Taylor, J.H., 1986, preprintGoogle Scholar
  27. 27.
    Alpar, M.A., and Shaham J., 1985, Nature 316, 239ADSCrossRefGoogle Scholar
  28. 28.
    Van der Klis, M., Jansen, F., van Paradijs, J., Lewin, W.H.G., van den Heuvel, E.P.J., Trumper, J.E. and Sztajano, M., 1985, Nature 316, 225Google Scholar
  29. 29.
    Lamb, F.K., Shibashaki, N., Alpar, M.A. and Shaman, J., 1985, Nature 317, 681ADSCrossRefGoogle Scholar
  30. 30.
    Berman, N.M., and Stollman, G.M., 1986a, Astron. & Astrophys. 154, L23ADSGoogle Scholar
  31. 31.
    Lewin, W.H.G., 1986, talk presented at workshop on “The Physics of Accretion onto Compact Objects”, Tenerife, SpainGoogle Scholar
  32. 32.
    Stollman, G., and Kuperus, M., 1986, Astron. & Astrophys. (submitted)Google Scholar
  33. 33.
    Klezcek, J., and Kuperus, M., 1969, Solar Phys. 6, 72Google Scholar
  34. 34.
    Pringle, J.E., 1981, Ann. Rev. Astron. Astrophys. 19, 137ADSCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • M. Kuperus
    • 1
  1. 1.Observatory “Sonnenborgh”University of UtrechtUtrechtNetherlands

Personalised recommendations