Abstract
The fundamental hypothesis by Alfvén and Carlqvist (1967) that solar flares are related to electrical currents in the solar chromosphere and low corona is investigated in the light of modern observations. We confirm the important role of currents in solar flares. There must be tens of such current loops (‘flux threads’) in any flare, and this explains the hierarchy of bursts in flares. We summarize quantitative data on energies, numbers of particles involved and characteristic times. A special case is the high-energy flare: this one may originate in the same way as less energetic ones, but it occurs in regions with higher magnetic field strength. Because of the high particle energies involved their emission seats live only very briefly; hence the area of emission coincides virtually with the seat of the instability. These flares are therefore the best examples for studying the primary instability leading to the flare. Finally, we compare the merits of the original Alfvén-Carlqvist idea (that flares originate by current interruption) with the one that they are due to interaction (reconnection) between two or more fluxthreads. We conclude that a final decision cannot yet be made, although the observed extremely short time constants of flare bursts seem to demand a reconnection-type instability rather than interruption of a circuit.
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References
Alfvén, H.: 1977,Rev. Geophys. Space Phys. 15, 271.
Alfvén, H.: 1981,Cosmic Plasma, D. Reidel Publ. Co., Dordrecht, Holland.
Alfvén, H. and Carlqvist, P.: 1967,Solar Phys. 1, 220.
Batchelor, D. A., Crannell, C. J., Wiehl, H. J., and Magun, A.: 1985,Astrophys. J. 295, 258.
Carlqvist, P.: 1968, in Y. Öhman (ed.), ‘Mass Motions in Solar Flares and Related Phenomena’,Nobel Symp. 9, 193.
Carlqvist, P.: 1969,Solar Phys. 7, 377.
Carlqvist, P.: 1986,IEEE Transact. in Plasma Sci. PS14, 754.
De Jager, C.: 1985a,Solar Phys. 96, 143.
De Jager, C.: 1985b,Solar Phys. 98, 267.
De Jager, C.: 1986,Space Sci. Rev. 44, 43.
De Jager, C. and De Jonge, G.: 1978,Solar Phys. 58, 127.
De Jager, C. and Švestka, Z.: 1987,Adv. Space Res. 6, No. 6.
De Jager, C., Kuijpers, J., Correia, E., and Kaufmann, P.: 1987,Solar Phys. 110, 317.
De Jager, C., Machado, M. E., Schadee, A., Strong, K. T., Švestka, Z., Woodgate, B. E., and Van Tend, W.: 1983,Solar Phys. 84, 205.
Deszö, L. and Kovacs, A.: 1981,Publ. Debrecen Heliophys. Obs. 4, 35.
Donnelly, R. F. and Kane, S. R.: 1978,Astrophys. J. 222, 1043.
Duijveman, A., Hoyng, P., and Machado, M. E.: 1982,Solar Phys. 81, 137.
Gary, G. A., Moore, R. L., Hagyard, M. J., and Haisch, B. M.: 1987,Astrophys. J. (in press).
Hagyard, M. J. and Rabin, D. M.: 1986,Adv. Space Res. 6, No. 6, 7.
Kaufmann, P., Strauss, F. M., Opher, R., and Laporte, C.: 1980,Astron. Astrophys. 87, 58.
Kaufmann, P., Correia, E., Costa, J. E. R., Zodi Vaz, A. M., and Dennis, B. R.: 1985a,Nature 291.
Kaufmann, P., Correia, E., Costa, J. E. R., and Zodi Vaz, A. M.: 1985b,Astron. Astrophys. 157, 11.
Kiplinger, A. L., Dennis, B. R., Frost, K. J., and Orwig, L. E.: 1984,Astrophys. J. 287, L105.
Kundu, M. R., Gaizauskas, V., Woodgate, B. E., Schmahl, E. J., Shine, R., and Jones, H. P.: 1985Astrophys. J. Suppl. Ser. 57, 621.
Kundu, M. and Woodgate, B. E.: 1986,Energetic Phenomena on the Sun, NASA Conf. Publ. 2439.
Martens, P. H. C., Van den Oord, G. H. J., and Hoyng, P.: 1985,Solar Phys. 96, 235.
Martin, S. F., Deszö, L., Antalová, A., Kučera, A., and Harvey, L.: 1983,Adv. Space Res. 2(11), 39.
Moreton, G. and Severny, A.: 1968,Solar Phys. 3, 282.
Severny, A.: 1964,Space Sci. Rev. 3, 451.
Severny, A.: 1965,Astron. Zh. 42, 217.
Van Beek, H. F., De Feiter, L. D., and De Jager, C.: 1974,Space Res. XIV, 447.
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Paper dedicated to Professor Hannes Alfvén on the occasion of his 80th birthday, 30 May 1988.
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De Jager, C. Solar flares through electric current interaction. Astrophys Space Sci 144, 311–319 (1988). https://doi.org/10.1007/BF00793188
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DOI: https://doi.org/10.1007/BF00793188