Abstract
The paper summarizes observations of solar and space phenomena related to the McMath region Number 8461 which passed over the solar disk during the 1966 Proton Flare Project period, from August 21 to September 4, and produced two important solar particle events on August 28 and September 2. The most important results are reviewed and interpretation of some of them is suggested.
Items of particular interest: Occurrence of proton-active regions when two or more ‘rows’ of activity approach each other (Section 3). Possible stimulation of activity by magnetic fields of decaying regions that had been active before (4.2a, 5.1a). Significantly increased correlation of flares with X-ray bursts during the proton-active transit of the region (5.3b). Striking difference in the flare response in radio frequency range before and after August 26 (5.2b). Hardening of the X-rays (5.3a), increase in radio flux (5.2a), change in sunspot configuration (5.1c), and increased capability of the region for particle acceleration (5.1b, 5.2b), starting about three days prior to the proton flare. Clear evidence that some flares that occurred on or after August 26, but prior to the proton flare of August 28, already were sources of ≈ 1 MeV protons (5.2b, 8). Anomalous deficiency in metric component of radio bursts produced in the region (5.2c, 9.4d, 11.4b). Strong radio storm on meter waves immediately preceding the proton flare on August 28 (5.2a, 9.1b), coincident with preflare rising dark filament (9.1a) and slight preflare rise in flux of ≈ 1 MeV protons (10.2). Two phases of expansion (fast and slow) of the bright flare ribbons (9.2c). Coincidence of hard X-ray burst with the formation and fast separation of the bright flare ribbons. It is suggested that this is the time of particle acceleration in the flare (9.5b). Short-lived burst of UV radiation (9.6). Visible flare wave in the flare of August 28 (9.3b), and complexity of motions in this flare (9.4b). Suggested electron release by means of a blast wave (10.1a). Electron-proton splitting in the delayed shock-wave-associated maximum of the particle flux on August 29 (10.2c). First brightening of both proton flares in a similar position between the regions 8461 and 8459 (11.2c). Existence of a unique, low elevation coronal condensation three days after proton flare occurrences (7.2). Very strong flux of protons in energy range of the order of 100 MeV producing the largest PCA since July 1961, and unusually steep energy spectrum above 100 MeV in the flare of September 2 (12.2a, b, 12.4). Unusually long rise to the maximum flux, inconsistent with Burlaga's theory of anisotropic diffusion (12.2b). Interpretation of the undisturbed flux decay from September 2 to September 8 (12.2c). A corotating modulation phenomenon on September 8 (12.2d). Detection of medium nuclei, with He/M ratio 50 ± 11 (12.3a). Evidence against a purely velocity-dependent mode of particle propagation (12.3b). Electrons as the possible cause of the first PCA phase (12.4). Plasma disturbance due to permanent proton flux from the region (13.1). Electron injection into inner radiation belt during the geomagnetic storm associated with the September 2 flare (13.3).
Section 14 brings a time scheme of the most important phenomena associated with the complex of activity and the active region in question, and some unsolved problems of particular interest are pointed out in Section 15.
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References
Ageshin, P. N., Bayarevich, V. V., Stozhkov, Y. I., Charakhchyan, A. N., and Charakhchyan, T. N.: 1968, ‘The Proton Flares on July 7, September 2, 1966 and January 28, 1967’, Ann. IQSY 3, 282.
Alfvén, H. and Carlqvist, P.: 1967, Solar Phys. 1, 220.
Anderson, K. A.: 1969, ‘Electrons and Protons in Long-Lived Streams of Energetic Solar Particles’, Solar Phys. 6, 111.
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1968a, ‘The Observation of 10–50 keV Solar Flare X-Rays by the OGO Satellites and Their Correlation with Solar Radio and Energetic Particle Emission’, in IAU Symp. No. 35, p. 490.
Arnoldy, R. L., Kane, S. R., and Winckler, J. R.: 1968b, ‘An Atlas of 10–50 keV Solar Flare X-Rays Observed by the OGO Satellites, 5 September 1964 to 31 December 1966’, School of Physics and Astronomy, Univ. of Minnesota, CR-108.
Banin, V., De Feiter, L. D., Fokker, A. D., Martres, M. J., and Pick, M.: 1969, ‘On the Development and Activity of the Active Region Associated with the Proton Flare Event of 7 July 1966’, Ann. IQSY 3, 229.
Bartolini, U.: 1966, ‘SCNA and SEA’, Solar Phenomena, Roma, 104, 12, and 105, 12.
Biswas, S., Fichtel, C. E., and Guss, D. E.: 1962, Phys. Rev. 128, 2756.
Biswas, S., Fichtel, C. E., and Guss, D. E.: 1966, J. Geophys. Res. 71, 4071.
Böhme, A. and Krüger, A.: 1967, ‘Report on the Solar Events of the Period 1966 August 28–September 22’, Suppl. Ser. Observ. Data HHI, Vol. 1, No. 1.
Bruzek, A.: 1964, Astrophys. J. 140, 746.
Bryant, D. A., Cline, T. L., Desai, U. D., and McDonald, F. B.: 1965, Astrophys. J. 141, 478.
Bumba, V.: 1969, Extension of the Atlas of Solar Magnetic Fields, unpublished.
Burlaga, L. F.: 1967, J. Geophys. Res. 72, 4449.
Carigan, A. L. and Oliver, N. J.: 1966, Geophys. Space Data Bull. 3, 75.
Castelli, J. P. and Michael, G. A.: 1967, ‘The Sagamore Hill Solar Radio Observatory and the Event of August 28, 1966’, Solar Phys. 1, 125.
Castelli, J. P., Aarons, J., and Michael, G. A.: 1967, ‘Flux Density Measurements of Radio Bursts of Proton-Producing Flares and Nonproton Flares’, J. Geophys. Res. 72, 5491.
Castelli, J. P., Aarons, J., Michael, G. A., Jones, C., and Ko, H. C.: 1969, ‘Spectral Considerations of Microwave Solar Bursts’, in Solar Flares and Space Research (ed. C. de Jager and Z. Švestka), North Holland, Amsterdam, p. 194.
Catalogue of Disturbances in Ionosphere, Geomagnetic Field, Field Intensity of Radio Wave, Cosmic Ray, Solar Phenomena and Other Related Phenomena (August 29–September 4, 1966): 1967, Rep. Iono. Space Res. Japan 21, 257.
Charakhchyan, A. N. and Stozhkov, Y. I.: 1968, ‘The Solar Cosmic Rays on September 2, 1966’, preprint.
Cline, T. L. and McDonald, F. B.: 1968, ‘Relativistic Electrons from Solar Flares’, Solar Phys. 5, 507.
Cline, T. L., Holt, S. S., and Hones, E. W.: 1968, J. Geophys. Res. 73, 434.
De Jager, C.: 1968, Mass Motions in Solar Flares and Related Phenomena, Nobel Symposium 9, 171.
Dodson, H. W. and Hedeman, E. R.: 1968, ‘The Proton Flare of August 28, 1966’, Solar Phys. 4, 229.
Dodson, H. W. and Hedeman, E. R.: 1969, ‘Later Development of the Center of Activity of the Proton Flare, July 7, 1966’, Ann. IQSY 3, 215.
Dodson, H. W., Hedeman, E. R., Kahler, S. W., and Lin, R. P.: 1969, ‘The Solar Particle Event of July 16–19, 1966 and its Possible Association with a Flare on the Invisible Solar Hemisphere’, Solar Phys. 6, 294.
Dollfus, A.: 1968, ‘Observation des jets et concentrations de la couronne au-dessus des régions actives’, in IAU Symp. No 35, 359.
Donnelly, R. F.: 1968, ‘The X-Ray and Extreme Ultraviolet Radiation of the August 28, 1966 Proton Flare as Deduced from SID Data’, Solar Phys. 5, 123.
Durgaprasad, N., Fichtel, C. E., Guss, D. E., and Reames, D. V.: 1968, ‘Nuclear-Charge Spectra and Energy Spectra in the September 2, 1966, Solar-Particle Event’, Astrophys. J. 154, 307.
Eliseev, G. F. and Moiseev, I. G.: 1965, Izv. Krymsk. Astrofiz. Observ. 34, 3.
Fan, C. Y., Pick, M., Pyle, R., Simpson, J. A., and Smith, D. R.: 1968, ‘Protons Associated with Centers of Solar Activity and Their Propagation in Interplanetary Magnetic Field Regions Corotating with the Sun’, J. Geophys. Res. 73, 1555.
Fortini, T. and Torelli, M.: 1968, IAU Symp. No. 35, 50.
Friedman, H.: 1969, ‘X-Ray Observations of Solar Flares’, in Solar Flares and Space Research (ed. C. de Jager and Z. Švestka), North Holland, Amsterdam, p. 87.
Ginzburg, V. L. and Syrovatsky, S. I.: 1965, Ann. Rev. Astron. Astrophys. 3, 297.
Gloeckler, G. and Jokipii, J. R.: 1966, Phys. Rev. Letters 17, 203.
Gnevyshev, M. N.: 1969, ‘Coronal Data for the Period of the Proton Flare Event of July 1966’, Ann. IQSY 3, 47.
Godoli, G. and Monsignori Fossi, B. C.: 1968, ‘The Ca Plage of the Active Region No. 18521 (25N 184°) of the Proton Flares of August, 28th and September 2nd, 1966’, Publ. Oss. Astrofis. Catania, Nuova Serie N. 122.
Godoli, G., Mazzucconi, F., and Nagasawa, S.: 1968, ‘The Limb Activity on September 4, 1966 of the Active Region No. 18521 (25N 184°) of the Proton Flares of August 28th and September 2nd’, Publ. Oss. Astrofis. Catania, Nuova Serie N. 123.
Gosling, J. T., Asbridge, J. R., Same, S. J., Hundhausen, A. J., and Strong, I. B.: 1968, J. Geophys. Res. 73, 43.
Greenfield, S. M. and Venkateswaran, S. V.: 1967, ‘The Vertical Structure of Dynamo Winds Deduced from Geomagnetic Variations Associated with Solar Flares’, Paper presented at the Birkeland Symp. on Aurora and Magn. Storms, Sandefjord, Norway.
Hakura, Y.: 1967, J. Geophys. Res. 72, 1461.
Haurwitz, M. W., Yoshida, S., and Akasofu, S. I.: 1965, J. Geophys. Res. 70, 2977.
Hofmann, D. J. and Winckler, J. R.: 1963, J. Geophys. Res. 68, 2067.
Howard, R.: 1963, Astrophys. J. 138, 1312.
Howard, R.: 1969, Solar Phys. 6, 154.
Howard, R., Bumba, V., and Smith, S. F.: 1967, Atlas of Solar Magnetic Fields, Carnegie Inst. Washington Publ. 626.
Hultqvist, B.: 1969, ‘Polar Cap Absorption and Ground Level Effects’, in Solar Flares and Space Research (ed. C. de Jager and Z. Švestka), North Holland, Amsterdam, p. 215.
Hyder, Ch.L.: 1967a, ‘A Phenomenological Model for Disparitions Brusques Followed by Flarelike Chromospheric Brightenings, I’, Solar Phys. 2, 49.
Hyder, Ch.L.: 1967b, ‘A Phenomenological Model for Disparitions Brusques Followed by Flarelike Chromospheric Brightenings, II’, Solar Phys. 2, 267.
Kane, S. R. and Winckler, J. R.: 1969, ‘Observations of Energetic X-Rays and Solar Cosmic Rays Associated with the 23 May 1967 Solar Flare Event’, Solar Phys. 6, 304.
Kane, S. R., Winckler, J. R., and Hofmann, D. J.: 1969, ‘Observations of the Screening of Solar Cosmic Rays by the Outer Magnetosphere’, Planet. Space Sci., in press.
Khetsuriani, T. S.: 1967, ‘Optical Observations of Flares of August 28th and September 2nd at Abastumani Observatory’, unpublished.
Kinsey, J. H. and McDonald, F. B.: 1968, ‘Observations of the Solar Proton Event of 28 August 1966’, in IAU Symp. No. 35, 536.
Konstantinov, V. A.: 1967, ‘Powerful Flare of Solar Activity on September 2, 1966 by the Observation Results in Alma-Ata’, Geomagnetizm i Aeronomia 7, 876.
Korchak, A. A.: 1967, Sov. Astron. 11, 258.
Křivský, L.: 1963, Bull. Astr. Inst. Czech. 14, 77.
Křivský, L. and Nestorov, G.: 1968, ‘Development of Proton Region with Flares and Ionospheric Effects (26.7–5.9. 1966)’, Bull. Astr. Inst. Czech. 19, 197.
Křivský, L. and Nestorov, G.: 1969, ‘Ionospheric Effects of X-Ray Emission from an Active Region with a Proton Flare (30 June–11 July 1966)’, Ann. IQSY 3, 137.
Křivský, L. and Obridko, V.: 1969, Solar Phys. 6, 418.
Krüger, A.: 1969, ‘Remarks on the Slowly Varying Component of Solar Radio Emission during the PFP Period of July, 1966’, Ann. IQSY 3, 70.
Lambert, D.: 1967, Nature 215, 43.
Lazutin, L. L. and Kuzmin, I. A.: 1967, ‘Solar Cosmic Rays on September 1966 Measured at Balloon Altitudes’, Sparmo Bull.
Legrand, J. P.: 1960, Ann. Geophys. 16, 140.
Lin, R. P. and Anderson, K. A.: 1967, ‘Electrons > 40 keV and Protons > 500 keV of Solar Origin’, Solar Phys. 1, 446.
Lindgren, S. T.: 1968, ‘The Solar Particle Events of May 23 and May 28, 1967’, Solar Phys. 5, 382.
Martres, M. J.: 1968, IAU Symp. No. 35, 25.
Martres, M. J. and Pick, M.: 1962, Ann. Astrophys. 25, 293.
Masley, A. J. and Goedeke, A. D.: 1967, ‘The 1966–1967 Increase in Solar Cosmic Ray Activity’, Tenth Intern. Conf. on Cosmic Rays, Calgary, June 1967.
Matveeva, E. T. and Troitzkaya, V. A.: 1969, Ann. IQSY 3, 408.
McClinton, A. T.: 1968, ‘White Light Flares’, NR L Space Research Seminar, April 17, 1968, p. 63.
McCracken, K. G.: 1969, in Solar Flares and Space Research (ed. C. de Jager and Z. Švestka), North Holland, Amsterdam, p. 202.
McCracken, K. G., Rao, U. R., and Bukata, R. P.: 1967, ‘Cosmic Ray Propagation Processes I’, J. Geophys. Res. 72, 4293.
Mogilevsky, E. L., Demkina, L. B., Dolginova, Y. N., Ioshpa, B. A., Obridko, V. N., Shelting, B. D., and Zhulin, I. A.: 1969, ‘Magnetic Field Decay in the Group 21034’, Ann. IQSY 3, 222.
Ness, N. F. and Taylor, H. E.: 1969, Ann. IQSY 3, 366.
Newkirk, G.: 1961, Astrophys. J. 133, 983.
Newkirk, G., Hansen, R. T., and Hansen, S.: 1969, ‘Coronal Electron Densities during the Period of the July 1966 Proton Flare’, Ann. IQSY 3, 49.
Pintér, S.: 1968, ‘Direct Geomagnetic Effects of the Proton Flares of August 28 and September 2, 1966’, unpublished.
Pfitzer, K. and Winckler, J. R.: 1968, ‘Experimental Observation of a Large Addition to the Electron Inner Radiation Belt after a Solar Flare Event’, J. Geophys. Res. 73, 5792.
Ramsey, H. E. and Smith, S. F.: 1966, Contract No. N00014-66-C-0059 for the Off. of Nav. Res. Dept. of the Navy, Washington, LR 20444, December.
Reid, G. C.: 1964, J. Geophys. Res. 69, 2659.
Sawyer, C.: 1968, ‘Sunspot Changes Following Proton Flares’, in IAU Symp. No. 35, 543.
Severny, A. B.: 1969a, Ann. IQSY 3, 11.
Severny, A. B.: 1969b, ‘Solar Flares and Magnetic Fields’, in Solar Flares and Space Research (ed. C. de Jager and Z. Švestka), North Holland, Amsterdam, p. 38.
Shimabukuro, F. I.: 1968, ‘A Comparison of 3.3 mm Bursts and Hα Emission during Flares’, Solar Phys. 5, 498.
Simon, P. and Švestka, Z.: 1969, ‘General Summary on the Results of the First Proton Flare Project Period, July 1966’, Ann. IQSY 3, 469.
Sivaraman, K. R.: 1969, Solar Phys. 6, 152.
Smart, D. F. and Shea, M. A.: 1969, ‘Proposed Solar Proton Classification System’, presented at the IUCSTP Symposium, London, January 1969.
Smith, S. F. and Ramsey, H. E.: 1964, Z. Astrophys. 60, 1.
Stewart, R. T.: 1968, ‘The Dynamic Spectrum of the Proton Event of September 2nd, 1966’, unpublished.
Švestka, Z.: 1968a, Solar Phys. 4, 18.
Švestka, Z.: 1968b, IAU Symp. No. 35, 287.
Švestka, Z.: 1968c, ‘Proton Flare Project’, IAU Symp. No. 35, 513.
Švestka, Z.: 1968d, Mass Motions in Solar Flares and Related Phenomena, Nobel Symp. 9, 17.
Švestka, Z.: 1968e, Solar Phys. 4, 361.
Takao, K.: 1967, ‘X-Ray Events at the End of August, 1966’, Rep. Ion. Space Res. Japan 21, 125.
Taylor, H. E.: 1969, ‘Sudden Commencement Associated Discontinuities in the Interplanetary Magnetic Field Observed by IMP 3’, Solar Phys. 6, 320.
Torelli, M.: 1966, ‘Heliographic Position, Classification and Area of Sunspot-Groups’, Solar Phenomena, Roma, 106, 2.
Valniček, B.: 1967, Bull. Astron. Inst. Czech. 18, 249.
Van Allen, J. A.: 1967, ‘Soft X-Ray (λ < 14 Å) Emission by the Sun since 1 July 1966’, unpublished.
Warwick, J. W.: 1968, ‘Decametric Radio Spectra and Positions during the Flare of August 28, 1966’, Solar Phys. 4, 446.
Weiss, A. A.: 1963, Australian J. Phys. 16, 240.
Yudin, O. and Kai, K.: 1969, Ann. IQSY 3, 124.
Zirin, H. and Lackner, D. Russo: 1969, ‘The Solar Flares of August 28 and 30, 1966’, Solar Phys. 6, 86.
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Švestka, Z., Simon, P. Proton Flare Project, 1966. Sol Phys 10, 3–59 (1969). https://doi.org/10.1007/BF00146153
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DOI: https://doi.org/10.1007/BF00146153