Abstract
Scattering of radio waves by density fluctuations in the solar wind leads to rapid variation in the intensity of compact radio sources. This phenomenon, known as Interplanetary Scintillation (IPS), provides a simple method to study interplanetary activity in the inner heliosphere. During the solar maximum of cycle 22, we carried out extensive, high-time-resolution IPS observations of fast moving interplanetary plasma clouds (IPCs). The observations were done using the Ooty Radio Telescope (ORT) and covered the region between 0.2 AU and 0.8 AU around the Sun. We detected 33 IPCs having velocities of 600 to 1400 km s−1. A two-component model of scattering by time-varying solar wind was developed to analyse these IPCs. The model enabled us to estimate the mass, energy and geometry of each disturbance and to associate them with solar-geomagnetic activity.
Detailed analysis suggests that these IPCs were interplanetary signatures of massive and energetic Solar Mass Ejections (SMEs). The SMEs were found to have average mass and kinetic energy of 5.3×1016 g, 2.4×1032 ergs. The average span and width of the SME was found to be 42° and 8×106 km. Association of these disturbances with solar-geomagnetic activity shows that about 80% of them are associated with Long-Duration X-ray Events (LDXE) and Solar Mass Ejections (SMEs). Only 50% of the events were associated with geomagnetic activity. The present experiment has demonstrated that continuous IPS monitoring is an effective technique to detect mass ejections in the interplanetary medium and to study their evolution through the inner heliosphere.
Similar content being viewed by others
References
Bird, M. K., Volland, H., Patzold, M., Edenhofer, P., Asmar, S. W., and Brenklre, J. P.: 1994, Astrophys. J. 426, 373.
Bravo, S. and Nikiforova, E.: 1994, Solar Phys. 151, 333.
Bravo, S., Mendoza, B., and Perez-Enriquez: 1991, J. Geophys. Res. 96, 5387.
Burlaga, L. F.: 1991, in R. Schwenn and E. Marsch (eds.), Physics of the Inner Heliosphere, Vol. II, Springer-Verlag, Berlin.
Burlaga, L. F., Sitter, E., Mariani, F., and Schwenn, R.: 1981, J. Geophys. Res. 86, 6673.
Coles, W. A., Rickett, B. J., and Rumsey, V. H.: 1974, in Russell et al. (eds.) Proc. Solar Wind III 1, 351.
Detman, T. R., Dryer, M., and Leinbach, H.: 1991, in Marsch et al. (eds.), Proc. Solar Wind VII, 169.
Dryer, M.: 1982, Space Sci. Rev. 33, 233.
Fainshtein, V. G.: 1992, Sol.Phys. 137, 329.
Gapper, G. R., Hewish, A., Purvis, A., and Duffett-Smith, P. J.: 1982, Nature 296, 633.
Gosling, J. T.: 1993, J. Geophys. Res. 98, 18937.
Gosling, J. T., Hildner E., MacQueen, R. M., Munro, R. M., Poland, A. I., and Ross, C. L.: 1976, Solar Phys. 48, 389.
Harrison, R. A.: 1990, Solar Phys. 126, 185.
Hewish, A.: 1990, J. Geophys. Res. 95, 12301.
Hewish, A. and Bravo, S.: 1986, Solar Phys. 106, 185.
Hewish, A., Tappin, S. J., and Gapper, G. R.: 1985, Nature 314, 137.
Howard, R. A., Sheeley, N. R., Jr. Koomen, M.J., and Michels, D. J.: 1985, J. Geophys. Res. 90, 8173.
Hundhausen, A. J.: 1972, Coronal Expansion and Solar Wind, Springer-Verlag, New York.
Hundhausen, A. J. and Gentry, R. A.: 1969, J. Geophys. Res. 74, 2908.
Illing, R. M. E.: 1984, Astrophys. J. 280, 399.
Jackson, B. V. and Hildner E.: 1978, Solar Phys. 60, 155.
Janardhan, P., Balasubramanian, V., Ananthakrishnan, S., Dryer, M., Bhatnagar, A., and McIntosh, P. S.: 1996, Solar Phys. 166, 379.
Kahler, S.W. and Moses, D.: 1990, Astrophys. J. 362, 728.
Krieger, A. S.:1977, in J. B. Zirker (ed.), Coronal Holes and High Speed Wind Streams, p. 77.
Low, B.C.: 1982, Astrophys. J. 254, 796.
Low, B.C.: 1996, Solar Phys. 167, 217.
MacQueen, R. M. and Fisher, R. R.: 1983, Solar Phys. 89, 89.
Manoharan, P. K. and Ananthakrishnan, S.: 1990, Monthly Notices Royal Astron. Soc. 244, 691.
Monoharan, P. K., Ananthakrishnan, A., Dryer, M., Detman, T. R., Leinbach, H., Kojima, M., Watanabe, T., and Kahn, J.: 1995, Solar Phys. 156, 377.
Neugebauer, M.: 1989, Proc. Solar Wind VI 1, 243.
Nolte, J. T., Krieger, A. S., Timothy, A. F., Gold, R. E., Roelof, E. C., Vaiana, G., Lazarus, A. J., Sullivan, J. D., and McIntosh, P. S.: 1976, Solar Phys. 46, 303.
Rust, D. M., Hildner, E., et al.: 1980, in P. A. Sturrock et al. (eds.), Solar Flares: Skylab Workshop II, p. 273.
Schwenn, R.: 1995, Proc.of Solar Wind Eight, p. 426.
Schwenn, R.: 1996, Astrophys. Space Sci. 243/1, 187.
Sheeley, N. R., Jr., Howard, R. A., Koomen, M. J., Michels, D. J., Harvey, K. L., and Harvey, J. W.: 1982, Space Sci. Rev. 33, 219.
Sheeley, N. R., Jr., Howard, R. A., Koomen, M. J., Michels, D. J., Schwenn, R., Muhlhauser, K. H., and Rosenbauer, H.: 1985, J. Geophys. Res. 90, 163.
Sime, D., MacQueen, R. M., and Hundhausen, A. J.: 1984, J. Geophys. Res. 89, 2113.
Spangler, S. R., Sakurai, T., Coles, W. A., Grall, R. R., and Harmon, J. K.: 1995, in D. Winterhalter et al. (eds.), Solar Wind VIII Conf. Proc., p. 540.
Swarup, G., Sarma, N. V. G., Joshi, M. N., Kapahi, V. K., Bagri, D. S., Damle, S. H., Ananthakrishnan, S., Balasubramanian, V., Bhave, S. S., and Sinha, R. P.: 1971, Nature Phys. Sci. 230, 185.
Tappin, S. J., Hewish, A., and Gapper, G. R.: 1983, Planetary Space Sci. 31, 1171.
Wagner, W. J.: 1984, Ann. Rev. Astron. Astrophys. 22, 267.
Watanabe, T. and Kakinuma, T.: 1972, Publ. Astron. Soc. Japan 24, 459.
Webb, D. F., Howard, R. A., and Jackson, B. V.: 1995, in D. Winterhalter et al. (eds.), Solar Wind VIII Conf. Proc. 1, 540.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gothoskar, P., Rao, A. On observing mass ejections in the interplanetary medium. Solar Physics 185, 361–390 (1999). https://doi.org/10.1023/A:1005114622634
Issue Date:
DOI: https://doi.org/10.1023/A:1005114622634