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Initial ISEE magnetometer results: magnetopause observations

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Abstract

The magnetic field profiles across the magnetopause obtained by the ISEE-1 and -2 spacecraft separated by only a few hundred kilometers are examined for four passes. During one of these passes the magnetosheath field was northward, during one it was slightly southward, and in two it was strongly southward. The velocity of the magnetopause is found to be highly irregular ranging from 4 to over 40 km s-1 and varying in less time than it takes for a spacecraft to cross the boundary. Thicknesses ranged from 500 to over 1000 km.

Clear evidence for reconnection is found in the data when the magnetosheath field is southward. However, this evidence is not in the form of classic rotational discontinuity signatures. Rather, it is in the form of flux transfer events, in which reconnection starts and stops in a matter of minutes or less, resulting in the ripping off of flux tubes from the magnetosphere. Evidence for flux transfer events can be found both in the magnetosheath and the outer magnetosphere due to their alteration of the boundary normal. In particular, their presence at the time of magnetopause crossings invalidates the usual 2-dimensional analysis of magnetopause structure. Not only are these flux transfer events probably the dominant means of reconnection on the magnetopause, but they may also serve as an important source of magnetopause oscillations, and hence of pulsations in the outer magnetosphere. On two days the flux transfer rate was estimated to be of the order of 2 × 1012 Maxwells per second by the flux transfer events detected at ISEE. Events not detectable at ISEE and continued reconnection after passage of an FTE past ISEE could have resulted in an even greater reconnection rate at these times.

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References

  1. Arnoldy, R. L.: 1971, ‘Signature in the Interplanetary Medium for Substorms’, J. Geophys. Res. 76, 5189.

  2. Aubry, M. P., Russell, C. T., and Kivelson, M. G.: 1970, ‘Inward Motion of the Magnetopause Before a Substorm’, J. Geophys. Res. 75, 7018.

  3. Aubry, M. P., Kivelson, M. G., and Russell, C. T.: 1971, ‘Motion and Structure of the Magnetopause’, J. Geophys. Res. 76, 1673.

  4. Binsack, J. H.: 1968, ‘Shock and Magnetopause Boundary Observations with IMP-2’, in R. L. Carovillano, J. F. McClay, and H. R. Radoski (eds.), Physics of the Magnetosphere, D. Reidel Publ. Co., Dordrecht, p. 605.

  5. Boller, B. R. and Stolov, H. L.: 1970, ‘Kelvin-Helmholtz Instability and the Semi-Annual Variation of Geomagnetic Activity’, J. Geophys. Res. 75, 6073.

  6. Boller, B. R. and Stolov, H. L.: 1973, ‘Explorer-18 Study of the Stability of the Magnetopause Using a Kelvin-Helmholtz Instability Criterion’, J. Geophys. Res. 78, 8078.

  7. Bridge, H., Egidi, A., Lazarus, A., Lyon, E., and Jacobson, L: 1965, ‘Preliminary Results of Plasma Measurements on IMP-A’, Space Research V, North-Holland Publ. Co., Amsterdam, p. 969.

  8. Burton, R. K., McPherron, R. C., and Russell, C. T.: 1975, ‘An Interplanetary Relationship Between Interplanetary Conditions and Dst’, J. Geophys. Res. 80, 4204.

  9. Cahill, L. J. and Amazeen, P. G.: 1963, ‘The Boundary of the Geomagnetic Field’, J. Geophys. Res. 68, 1835.

  10. Cahill, L. J. and Patel, V. L.: 1967, ‘The Boundary of the Geomagnetic Field, August to November, 1961’, Planetary Space Sci. 15, 997.

  11. Cummings, W. D. and Coleman, P. J., Jr.: 1968, ‘Magnetic Fields in the Magnetopause and Vicinity at Synchronous Altitude’, J. Geophys. Res. 73, 5699.

  12. Fairfield, D. H.: 1971, ‘Average and Unusual Locations of the Earth's Magnetopause and Bow Shock’, J. Geophys. Res. 76, 6700.

  13. Feldstein, Y. L: 1970, ‘Auroras and Associated Phenomena’, in E. R. Dyer (ed.), Solar Terrestrial Physics, Part III, D. Reidel Publ. Co., Dordrecht, p. 152.

  14. Frank, L. A. and Van Allen, J. A.: 1964, ‘Intensity of Electrons in the Earth's Inner Radiation Zone’, J. Geophys. Res. 69, 4923.

  15. Freeman, J. W., Jr.: 1964, ‘Detection of an Intense Flux of Low-Energy Protons or Ions Trapped in the Inner Radiation Zone’, J. Geophys. Res. 69, 1691.

  16. Gosling, J. T., Asbridge, J. R., Bame, S. J., and Strong, I. B.: 1967, ‘Vela-2 Measurements of the Magnetopause and Bow Shock Positions’, J. Geophys. Res. 72, 101.

  17. Haerendel, G., Paschmann, G., Sckopke, N., Rosenbauer, H., and Hedgecock, P. C.: 1978, ‘The Frontside Boundary Layer of the Magnetosphere and the Problem of Reconnection’, J. Geophys. Res. 83, 3195.

  18. Heppner, J. P., Sugiura, M., Skillman, T. L., Ledley, B. G., and Campbell, M.: 1967, ‘OGO-A Magnetic Field Observations’, J. Geophys. Res. 72, 5417.

  19. Holzer, R. E. and Slavin, J. A.: 1978, ‘Magnetic Flux Transfer Associated with Expansions and Contractions of the Dayside Magnetosphere’, J. Geophys. Res. 83, 3831.

  20. Holzer, R. E., McLeod, M. G., and Smith, E. J.: 1966, ‘Preliminary Results from the OGO-1 Search Coil Magnetometer: Boundary Positions and Magnetic Noise Spectra’, J. Geophys. Res. 71, 1481.

  21. Kaufmann, R. L. and Konradi, A.: 1969, ‘Explorer-12 Magnetopause Observations: Large-Scale Non-Uniform Motion’, J. Geophys. Res. 74, 3609.

  22. Kaufmann, R. L. and Konradi, A.: 1973, ‘Speed and Thickness of the Magnetopause’, J. Geophys. Res. 78, 6549.

  23. Ledley, B. G.: 1971, ‘Magnetopause Attitudes During OGO-5 Crossings’, J. Geophys. Res. 76, 6736.

  24. Meng, G.-I.: 1970, ‘Variation of the Magnetopause Position with Substorm Activity’, J. Geophys. Res. 75, 3252.

  25. Mozer, F. S., Torbert, R. B., Fahleson, U. V., Fälthammar, C.-G., Gonfalone, A., Pedersen, A., and Russell, C. T.: 1978, Geophys. Res. Letters, submitted.

  26. Ness, N. F., Sceorce, C. S., and Seek: 1964, ‘Initial Results of the IMP-1 Magnetic Field Experiment’, J. Geophys. Res. 69, 3531.

  27. Ness, N. F.: 1967, in J. W. King and W. S. Newman (eds.), Solar Terrestrial Physics, Academic Press, London, p. 57.

  28. Neugebauer, M., Russell, C. T., and Smith, E. J.: 1974, ‘Observations of the Internal Structure of the Magnetopause’, J. Geophys. Res. 79, 499.

  29. Ogilvie, K. W., Scudder, J. D., and Sugiura, M.: 1971, ‘Magnetic Field and Electron Observations Near the Dawn Magnetopause’, J. Geophys. Res. 76, 3574.

  30. Paschmann, G., Sckopke, N., Haerendel, G., Papamastorakis, J., Bame, S. J., Asbridge, J. R., Gosling, J. T., Hones, E. W., Jr, and Tech, E. R.: 1978, ‘ISEE Plasma Observations Near the Subsolar Magnetopause’, Space Sci. Rev. 22, 717.

  31. Patel, V. L. and Dessler, A. J.: 1966, ‘Geomagnetic Activity and Size of Magnetospheric Cavity’, J. Geophys. Res. 71, 1940.

  32. Russell, C. T.: 1978, ‘The ISEE-1 and -2 Fluxgate Magnetometers’, IEEE Trans. Geosci. Electr. GE-16, 239.

  33. Russell, C. T. and Greenstadt, E. W.: 1979, ‘Initial ISEE Magnetometer Results: Shock Observations,’ Space Sci. Rev. 23, in press.

  34. Russell, C. T. and McPherron, R. L.: 1973, ‘The Magnetotail and Substorms’, Space Sci. Rev. 15, 205.

  35. Russell, C. T., Neugebauer, M., and Kivelson, M. G.: 1974, ‘OGO-5 Observations of the Magnetopause’, in D. E. Page (ed.), Correlated Interplanetary and Magnetospheric Observations, D. Reidel Publ. Co., Dordrecht, p. 139.

  36. Sonnerup, B. U. O.: 1971, ‘Magnetopause Structure During the Magnetic Storm of September 24, 1961’, J. Geophys. Res. 76, 6717.

  37. Sonnerup, B. U. O. and Cahill, L. J., Jr.: 1967, ‘Magnetopause Structure and Attitude from Explorer-12 Observations’, J. Geophys. Res. 72, 171.

  38. Sonnerup, B. U. O. and Cahill, L. J., Jr.: 1968, ‘Explorer-12 Observations of the Magnetopause Current Layer’, J. Geophys. Res. 73, 1757.

  39. Sonnerup, B. U. O. and Ledley, B. G.: 1974, ‘Magnetopause Rotational Forms’, J. Geophys. Res. 79, 4309.

  40. Sonnerup, B. U. O. and Ledley, B. G.: 1978, ‘OGO-5 Magnetopause Structure and Classical Reconnection’, J. Geophys. Res., submitted.

  41. Wolfe, J. H., Silva, R. W., and Meyers, M. A.: 1966, ‘Observations of the Solar Wind During the Flight of IMP-1’, J. Geophys. Res. 71, 1319.

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Russell, C.T., Elphic, R.C. Initial ISEE magnetometer results: magnetopause observations. Space Sci Rev 22, 681–715 (1978). https://doi.org/10.1007/BF00212619

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Keywords

  • Magnetic Field
  • Transfer Rate
  • Transfer Event
  • Flux Tube
  • Field Profile