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Impulsive (Flash) Phase of Solar Flares: Hard X-Ray, Microwave, EUV and Optical Observations

Published online by Cambridge University Press:  25 May 2016

S. R. Kane*
Affiliation:
Space Sciences Laboratory, University of California, Berkeley, Calif. 94720, U.S.A.

Abstract

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Recent observations of impulsive hard X-ray, microwave, EUV and optical emissions during solar flares are briefly reviewed in order to deduce the characteristics of the impulsive (flash) phase phenomenon in small solar flares particularly from the point of view of the acceleration of electrons and their role in producing the various impulsive phase emissions. Observed and deduced characteristics of the various electromagnetic emission sources are summarized (Table II). The deduced characteristics of the electron acceleration process (Table III) indicate a process with high acceleration efficiency. The observations are found to be consistent with a model in which electrons are accelerated in a series of short pulses each lasting for ≲ 1 s and the accelerated electrons provide the energy necessary for all the observed electromagnetic emissions produced during the flash phase of small solar flares. Models of the impulsive phase emissions in which energetic electrons play a prominant role are examined and crucial tests to check the accuracy of these models are indicated (Table IV).

Type
Part II The Flash Phase of Solar Flares
Copyright
Copyright © Reidel 1974 

References

Acton, L. W.: 1968, Astrophys. J. 152, 305.CrossRefGoogle Scholar
Akalane, K.: 1956, Publ. Astron. Soc. Japan 8, 173.Google Scholar
Alfvén, H. and Carlqvist, P.: 1967, Solar Phys. 1, 220.Google Scholar
Anderson, K. A., Kane, S. R., and Lin, R. P.: 1970, ‘Fast Electrons from Solar Flares’, presented at the International Seminar on the Problem of Cosmic Ray Generation on the Sun, Leningrad, U.S.S.R., December.Google Scholar
Anderson, K. A. and Winckler, J. R.: 1962, J. Geophys. Res. 67, 4103.Google Scholar
Angle, K. L.: 1968, Astron. J. 73, 553.Google Scholar
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1967, Solar Phys. 2, 171.Google Scholar
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1968a, Astrophys. J. 151, 711.Google Scholar
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1968b, in Kiepenheuer, K. O. (ed.), ‘Structure and Development of Solar Active Regions’, IAU Symp. 35, 490.Google Scholar
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1968c, Tech. Rep. CR-108, Cosmic Ray Group, School of Physics and Astronomy, Univ. of Minnesota, Minneapolis.Google Scholar
Axisa, F., Martres, M. J., Pick, M., and Soru-Escant, I.: 1973, Solar Phys. 29, 163.Google Scholar
Biswas, S. and Radhakrishman, B.: 1973, Solar Phys. 28, 211.Google Scholar
Boischot, A.: 1972, in Dyer, E. R. (ed.), Solar Terrestrial Physics/1970, D. Reidel Publ. Co., Dordrecht-Holland, p. 87.Google Scholar
Brown, J. C.: 1971, Solar Phys. 18, 489.Google Scholar
Brown, J. C.: 1972, Solar Phys. 25, 158.Google Scholar
Brown, J. C.: 1973, this volume, p. 395.Google Scholar
Bruzek, A.: 1964, in Hess, W. N. (ed.), AAS-NASA Symposium on the Physics of Solar Flares, NASA SP-50, p. 301.Google Scholar
Bruzek, A.: 1967, in Xanthakis, J. N. (ed.), Solar Physics, Interscience Publ., New York, p. 399.Google Scholar
Castelli, J. P. and Barron, W. R.: 1969, Bull. Am. Astron. Soc. 1, 274.Google Scholar
Castelli, J. P. and Richards, D. W.: 1971, J. Geophys. Res. 76, 8409.Google Scholar
Chubb, T. A.: 1972, in Dyer, E. R. (ed.), Solar Terrestrial Physics/1970, Part I, D. Reidel Publ. Co., Dordrecht-Holland, p. 99.Google Scholar
Chubb, T. A., Kreplin, R. W., and Friedman, H.: 1966, J. Geophys. Res. 71, 3611.Google Scholar
Cline, T. L., Holt, S. S., and Hones, E. W.: 1968, J. Geophys. Res. 73, 434.Google Scholar
Covington, A. E. and Harvey, G. A.: 1961a, Phys. Rev. Letters 6, 51.Google Scholar
Covington, A. E. and Harvey, G. A.: 1961b, Nature 192, 152.Google Scholar
Croom, D. L.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 114.Google Scholar
Datlowe, D. and Lin, R. P.: 1973, Solar Phys. 32, 459.Google Scholar
Datlowe, D. and Peterson, L. E.: 1973, ‘OSO-7 Observations of Solar X-Ray Bursts from 28 July to 9 August, 1972’, preprint.Google Scholar
Davies, K. and Donnelly, R. F.: 1966, J. Geophys. Res. 71, 2843.CrossRefGoogle Scholar
De Feiter, L. D.: 1972, Space Sci. Rev. 13, 827.Google Scholar
De Mastus, H. L. and Stover, R.: 1967, Publ. Astron. Soc. Pacific 79, 615.Google Scholar
Dodson, H. W., Hedeman, E. R., and McMath, R. R.: 1956, Astrophys. J. Suppl. 2, 241.Google Scholar
Dodson, H. W. and Hedeman, E. R.: 1968, Solar Phys. 4, 229.Google Scholar
Donnelly, R. F.: 1968, Solar Phys. 5, 123.Google Scholar
Donnelly, R. F.: 1969, Astrophys. J. Letters 158, L165.Google Scholar
Donnelly, R. F.: 1971, Solar Phys. 20, 188.Google Scholar
Donnelly, R. F.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30, 1972, NASA/GSFC Preprint X-693–73–193, p. 242.Google Scholar
Donnelly, R. F., Wood, A. T. Jr., and Noyes, R. W.: 1973, Solar Phys. 29, 107.Google Scholar
Doschek, G. A.: 1972, Space Sci. Rev. 13, 765.Google Scholar
Elcan, M. J.: 1973, Bull. Am. Astron. Soc. 5, 340.Google Scholar
Ellison, M. A.: 1947, Monthly Notices Roy. Astron. Soc. 109, 3.Google Scholar
Ellison, M. A.: 1963, Planetary Space Sci. 11, 597.Google Scholar
Elwert, G. and Haug, E.: 1970, Solar Phys. 15, 234.Google Scholar
Enome, S., Kakinuma, T., and Tanaka, H.: 1969, Solar Phys. 6, 428.Google Scholar
Enome, S. and Tanaka, H.: 1971, in Howard, R. (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 413.Google Scholar
Fainberg, J.: 1973, this volume, p. 183.Google Scholar
Frost, K. J.: 1964, in Hess, W. N. (ed.), AAS-NASA Symposium on the Physics of Solar Flares, NASA SP-50, 139.Google Scholar
Frost, K. J.: 1969, Astrophys. J. Letters 158, L159.Google Scholar
Frost, K. J., and Dennis, B. R.: 1971, Astrophys. J. 165, 655.Google Scholar
Gruber, D. E., Peterson, L. E., and Vette, J. I.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 147.Google Scholar
Guidice, D. A. and Castelli, J. P.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 87.Google Scholar
Hall, L. A.: 1971, Solar Phys. 21, 167.Google Scholar
Hall, L. A., and Hintuegger, H. E., 1969, in de Jager, C. and Švestka, Z. (eds.), ‘Solar Flares and Space Research’, COSPAR Symp., 81.Google Scholar
Harvey, G. A.: 1964, Astrophys. J. 139, 16.Google Scholar
Harvey, K. L.: 1971, Solar Phys. 16, 423.Google Scholar
Holt, S. S. and Ramaty, R.: 1969, Solar Phys. 8, 119.Google Scholar
Hudson, H. S.: 1972a, Solar Phys. 24, 414.Google Scholar
Hudson, H. S.: 1972b, paper presented at the Seminar on the Generality of Particle Acceleration of Various Scales in Cosmos, Leningrad, August 16–18, 1972.Google Scholar
Hudson, H. S.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on the High Energy Phenomena on the Sun, Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 207.Google Scholar
Hudson, H. S. and Ohki, K.: 1972, Solar Phys. 23, 155.Google Scholar
Hudston, H. S., Peterson, L. E., and Schwartz, D. A.: 1969, Astrophys. J., 157, 389.Google Scholar
Jager, C. de: 1960, in Bijl, H. K. (ed.), Space Research I, North Holl. Publ. Co., Amsterdam, p. 628.Google Scholar
Jager, C. de: 1962, Space Sci. Rev. 1, 487.Google Scholar
Jager, C. de: 1964, in Odishaw, H. (ed.), Research in Geophysics, Vol. 1, M.I.T. Press, Cambridge, Mass., Chapter 1.Google Scholar
Jager, C. de: 1969, in de Jager, C. and Švestka, Z. (eds.), ‘Solar Flares and Space Research’, COSPAR Symp. 1.Google Scholar
Jager, C. de and Kundu, M. R.: 1963, in Priestu, W. (ed.), Space Research III, North Holl. Publ. Co., Amsterdam, p. 836.Google Scholar
Kahler, S. W. and Kreplin, R. W.: 1971, Astrophys. J. 168, 531.CrossRefGoogle Scholar
Kahler, S. W., Meekins, J. F., Kreplin, R. W., and Boyer, L. S.: 1970, Astrophys. J. 162, 293.Google Scholar
Kakinuma, T., Yamashita, T., and Enome, S.: 1969, Proc. Res. Inst. Atmospherics, Nagoya Univ. Japan 16, 127.Google Scholar
Kane, S. R.: 1969, Astrophys. J. Letters 157, L139.CrossRefGoogle Scholar
Kane, S. R.: 1971, Astrophys. J. 170, 587.Google Scholar
Kane, S. R.: 1972a, Space Sci. Rev. 13, 822.CrossRefGoogle Scholar
Kane, S. R.: 1972b, Solar Phys. 27, 174.Google Scholar
Kane, S. R.: 1973a, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, Goddard Space Flight Center, Greenbelt, Maryland, September 28–30, 1972, NASA/GSFC Preprint X-693–73–193, p. 55.Google Scholar
Kane, S. R.: 1973b, paper presented at the 3rd Meeting of the Solar Physics Division of AAS, Las Cruces, New Mexico, Jan. 4–6.Google Scholar
Kane, S. R. and Anderson, K. A.: 1970, Astrophys. J. 162, 1003.Google Scholar
Kane, S. R. and Donnelly, R. F.: 1971, Astrophys. J. 164, 151.Google Scholar
Kane, S. R. and Hudson, H. S.: 1970, Solar Phys. 14, 414.Google Scholar
Kane, S. R., Kahler, S. W., and Kurfess, J. D.: 1972, Solar Phys. 25, 418.Google Scholar
Kane, S. R. and Lin, R. P.: 1972, Solar Phys. 23, 457.Google Scholar
Kane, S. R. and Winckler, J. R.: 1969a, Tech. Rep. CR-134, Cosmic Ray Group, School of Physics and Astronomy, Univ. of Minnesota, Minneapolis.Google Scholar
Kane, S. R. and Winckler, J. R.: 1969b, Solar Phys. 6, 304.CrossRefGoogle Scholar
Kelly, P. T. and Rense, W. A.: 1972, Solar Phys. 26, 431.Google Scholar
Kodama, M., Kusunosi, M., and Ogura, K.: 1971, Rep. Ionosphere Space Res. Japan 25, 285.Google Scholar
Korchak, A. A.: 1967, Soviet Astron. AJ, 11, 258.Google Scholar
Kundu, M. R.: 1961, J. Geophys. Res. 66, 4308.Google Scholar
Kundu, M. R.: 1965, Solar Radio Astronomy, Chaper 13, Interscience Publ., New York.Google Scholar
Kundu, M. R.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 104.Google Scholar
Lin, R. P.: 1970, ‘Acceleration of 10–100 keV Electrons in Solar Flares’, presented at Seminar on the Acceleration of Particles in Near-Earth and Interplanetary Space, Galaxy and Metagalaxy, Leningrad, U.S.S.R., July 13–15.Google Scholar
Lin, R. P.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 242.Google Scholar
Lin, R. P.: 1974a, Space Sci. Rev. 16, 189.Google Scholar
Lin, R. P.: 1974b, this volume, p. 201.Google Scholar
Lin, R. P. and Hudson, H. S.: 1971, Solar Phys. 17, 412.Google Scholar
Malville, J. M.: 1962, Astrophys. J. 135, 834.Google Scholar
Mandelstam, S. L.: 1972, Acta Physica Academiae Scientiarum Hungaricae 32, 307.Google Scholar
Maxwell, A.: 1965, in de Jager, C. (ed.), The Solar Spectrum, D. Reidel Publ. Co., Dordrecht, Holland, p. 342.Google Scholar
McIntosh, P. S. and Donnelly, R. F.: 1972, Solar Phys. 23, 444.Google Scholar
McKenzie, D. L.: 1972, Astrophys. J. 175, 481.Google Scholar
McKenzie, D. L., Datlowe, D., and Peterson, L. E.: 1973, Solar Phys. 28, 175.Google Scholar
McKenzie, D. L. and Peterson, L. E.: 1973, Bull. Am. Astron. Soc. 3, 340.Google Scholar
Moreton, G. E.: 1964, in Hess, W. N. (ed.), AAS-NASA Symposium on the Physics of Solar Flares, NASA-SP 50, p. 209.Google Scholar
Najita, K. and Orrall, F. Q.: 1970, Solar Phys. 15, 176.Google Scholar
Neupert, W. M.: 1971, Phil. Trans. Roy. Soc. London 270, 143.Google Scholar
Noyes, R. W.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on High Energy Phenomena on the Sun, held at Goddard Space Flight Center, Greenbelt, Maryland, September 28–30, 1972, NASA/GSFC Preprint X-693–73–193, p. 231.Google Scholar
Ohki, K. I.: 1969, Solar Phys. 7, 260.Google Scholar
Parks, G. K. and Winckler, J. R.: 1969, Astrophys. J. Letters 155, L117.Google Scholar
Parks, G. K. and Winckler, J. R.: 1971, Solar Phys. 16, 186.Google Scholar
Peterson, L. E. and Winckler, J. R.: 1959, J. Geophys. Res. 64, 697.Google Scholar
Peterson, L. E., Datlowe, D. W., and McKenzie, D. L.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on the High Energy Phenomena on the Sun, Goddard Space Flight Center, Greenbelt, Maryland, September 28–30 1972, NASA/GSFC Preprint X-693–73–193, p. 132.Google Scholar
Petrosian, V.: 1973, Astrophys. J. 186, 291.Google Scholar
Phillips, K. J. H.: 1973, Observatory 93, 17.Google Scholar
Phillips, K. J. H. and Neupert, W. M.: 1973, Solar Phys. 32, 209.Google Scholar
Pinter, S.: 1969, Solar Phys. 8, 142.Google Scholar
Ramaty, R. and Petrosian, V.: 1972, Astrophys. J. 178, 241.Google Scholar
Santangelo, N., Horstman, H., and Horstman-Moretti, E.: 1973, Solar Phys. 29, 143.Google Scholar
Smith, D. F.: 1973, this volume, p.Google Scholar
Smith, H. J. and Smith, E. v. P.: 1963, Solar Flares, The McMillan Co., New York.Google Scholar
Stewart, R. T.: 1973, this volume, p.Google Scholar
Sturrock, P. A.: 1968, in Kiepenheuer, K. O. (ed.), ‘Structure and Development of Solar Active Regions’, IAU Symp. 35, 471.Google Scholar
Sturrock, P. A.: 1973, this volume, p.Google Scholar
Švestka, Z.: 1969, in de Jager, C. and Švestka, Z. (eds.), ‘Solar Flares and Space Research’, COSPAR Symp., 16.Google Scholar
Švestka, Z.: 1970, Solar Phys. 13, 471.Google Scholar
Syrovatskii, S. I. 1969, in de Jager, C. and Švestka, Z. (eds.), ‘Solar Flares and Space Research’, COSPAR Symp., 346.Google Scholar
Syrovatskii, S. I. and Shmeleva, O. P.: 1971, Lebedev Institute Preprint 158.Google Scholar
Takakura, T.: 1968, Solar Phys. 6, 133.Google Scholar
Takakura, T.: 1969, in de Jager, C. and Švestka, Z. (eds.), ‘Solar Flares and Space Research’, COSPAR Symp., 165.Google Scholar
Takakura, T.: 1971, Solar Phys. 19, 186.Google Scholar
Takakura, T.: 1972, Solar Phys. 26, 151.Google Scholar
Takakura, T.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on the High Energy Phenomena on the Sun, Goddard Space Flight Center, Greenbelt, Maryland, September 28–30, 1972, NASA/GSFC Preprint X-693–73–193, p. 179.Google Scholar
Takakura, T. and Kai, K.: 1966, Publ. Astron. Soc. Japan 18, 57.Google Scholar
Takakura, T., Ohki, K., Shibuya, N., Fujii, M., Matsuoka, M., Miyamoto, S. Nishimura, J., Oda, M., Ogawara, Y., and Ota, S.: 1971, Solar Phys. 16, 454.Google Scholar
Tanaka, H., Kakinuma, T., and Enome, S.: 1967, Proc. Res. Inst. Atmospherics, Nagoya Univ. Japan 14, 23.Google Scholar
Tanaka, H. and Enome, S.: 1971, Solar Phys. 17, 408.Google Scholar
Tanaka, H. and Zirin, H.: 1973, in Ramaty, R. and Stone, R. G. (eds.), Proc. Symposium on the High Energy Phenomena on the Sun, Goddard Space Flight Center, Greenbelt, Maryland, September 28–30, 1972, NASA/GSFC Preprint X-693–73–193, p. 26.Google Scholar
Teske, R. G., Soyumer, T., and Hudson, H. S.: 1971, Astrophys. J. 165, 615.Google Scholar
Tindo, I. P., Ivanov, V. D., Mandelstam, S. L., and Shuryghin, A. I.: 1970, Solar Phys. 14, 204.Google Scholar
Tindo, I. P., Ivanov, V. D., Mandelstam, S. L., and Shyryghin, A. I.: 1972a, Solar Phys. 24, 429.CrossRefGoogle Scholar
Tindo, I. P., Ivanov, V. D., Valnicek, B., and Livshitz, M. A.: 1972b, Solar Phys. 27, 426.Google Scholar
Tomblin, F. F.: 1972, Astrophys. 171, 377.Google Scholar
Vette, J. I. and Casal, F. G.: 1961, Phys. Rev. Letters 6, 334.Google Scholar
Vorpahl, J. A.: 1972, Solar Phys. 26, 397.Google Scholar
Wild, J. P., Smerd, S. F., and Weiss, A. A.: 1963, Ann. Rev. Astron. Astrophys. 1, 291.Google Scholar
Winckler, J. R., May, T. C., and Masley, A. J.: 1961, J. Geophys. Res. 66, 316.Google Scholar
Wood, A. T. Jr. and Noyes, R. W.: 1972, Solar Phys. 24, 180.Google Scholar
Wood, A. T. Jr., Noyes, R. W., Dupree, A. K., Huber, M. C. E., Parkinson, W. H., Reeves, E. M., and Withbroe, G. L.: 1972, Solar Phys. 24, 169.Google Scholar
Zirin, H.: 1972, Solar Phys. 26, 393.Google Scholar
Zirin, H.: 1973, ‘Solar Flares’, review paper for Vistas in Astronomy 16, 1.Google Scholar
Zirin, H., Pruss, G., and Vorpahl, J.: 1971, Solar Phys. 19, 463.Google Scholar