Skip to main content
SpringerLink
Log in

Two Types of Gradual Events: Solar Protons and Relativistic Electrons

  • Published:
Geomagnetism and Aeronomy Aims and scope Submit manuscript

Abstract—

The gradual solar flares on April 21, 2002 (X1.5), and August 24, 2002 (X3.1), played an important role in the formation of the modern paradigm of acceleration of solar energetic particles (SEPs), according to which the difference in the observed composition of SEP ions is due to acceleration on a quasi-parallel (event of April 1–21) or quasi-perpendicular (event of August 2–24) shock wave. In our opinion, ions were accelerated not by shock waves but directly in parent flares, and it was the flare properties, in this case, their impulsive phases, that differed. Flare 1 had an unpronounced, impulsive phase, while Flare 2 had a pronounced impulse phase when the maximum intensity of microwave (μ) radiation was about an order of magnitude greater than that in Flare 1. Flare 2 experienced a rapid heating of plasma and an increase in the emission measure due to chromospheric evaporation, which can change the ion composition in the acceleration region. Simultaneous increases in the fluxes of relativistic electrons and protons with similar time profiles were observed in the interplanetary space (IS) after flares 1 and 2. However, there was an increase in the flux of relativistic electrons not accompanied by protons in the IS for the first 20 min only after Flare 2. These observational facts make it possible to introduce the gradual stochastic acceleration into the scenario of the considered events. In it, charged particles are accelerated in a set of elementary events that are shorter in duration than the full duration of the acceleration process.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.

Similar content being viewed by others

REFERENCES

  1. Belov, A., Kurt, V., Mavromichalaki, H., and Gerontidou, M., Peak-size distributions of proton fluxes and associated soft X-ray flares, Sol. Phys., 2007, vol. 246, no. 2, pp. 457–470.

    Article  Google Scholar 

  2. Benz, A.O., Radio spikes and the fragmentation of flare energy release, Sol. Phys., 1985, vol. 96, no. 2, pp. 357–370.

    Article  Google Scholar 

  3. Benz, A.O., Flare observations, Living Rev. Sol. Phys., 2017, vol. 14, id 2.

  4. Chertok, I.M., Diagnostic analysis of the solar proton flares of September, 2017, Geomagn. Aeron. (Engl. Transl.), 2018, vol. 58, no. 4, pp. 457–463.

  5. Cliver, E.W., Flare vs. shock acceleration of high-energy protons in solar energetic particle events, Astrophys. J., 2016, vol. 832, id 128.

  6. Cliver, E.W., Kahler, S.W., Kazachenko, M., and Shimojo, M., The disappearing solar filament of 2013 September 29 and its large associated proton event: Implications for particle acceleration at the Sun, Astrophys. J., 2019, vol. 877, id 11.

  7. Daibog, E.I., Melnikov, V.F., and Stolpovskii, V.G., Solar energetic particle events from solar flares with weak impulsive phases of microwave emission, Sol. Phys., 1993, vol. 144, pp. 361–372.

    Article  Google Scholar 

  8. Gallagher, P.T., Dennis, B.R., and Krucker, S., et al., RHESSI and Trace Observations of the 21 April 2002 ×1.5 flare, Sol. Phys., 2002, vol. 210, no. 1, pp. 341–356.

    Article  Google Scholar 

  9. Gallagher, P.T., Lawrence, G.R., and Dennis, B.R., Rapid acceleration of a coronal mass ejection in the low corona and implications for propagation, Astrophys. J., 2003, vol. 588, pp. L53–L56.

    Article  Google Scholar 

  10. Gopalswamy, N., Mäkelä, P., Akiyama, S., et al., Large solar energetic particle events associated with filament eruptions outside of active regions, Astrophys. J., 2015, vol. 806, id 8.

  11. Grechnev, V.V., Kiselev, V.I., Meshalkina, N.S., and Chertok, I.M., Relations between microwave bursts and near-Earth high-energy proton enhancements and their origin, Sol. Phys., 2015, vol. 290, pp. 2817–2855.

    Google Scholar 

  12. Grechnev, V.V., Kiselev, V.I., Uralov, A.M., et al., The 26 December 2001 solar eruptive event responsible for GLE63: III. CME, shock waves, and energetic particles, Sol. Phys., 2017, vol. 292, id 102.

  13. Kahler, S.W., Evidence for solar shock production of heliospheric near-relativistic and relativistic electron events, Space Sci. Rev., 2007, vol. 129, no. 4, pp. 359–390.

    Article  Google Scholar 

  14. Kocharov, L., Pohjolainen, S., and Mishev, A., et al., Investigating the origins of two extreme solar particle events: Proton source profile and associated electromagnetic emissions, Astrophys. J., 2017, vol. 839, no. 2, id 79.

  15. Kocharov, L., Pesce-Rollins, M., Laitinen, T., et al., Interplanetary protons versus interacting protons in the 2017 September 10 solar eruptive event, Astrophys. J., 2020, vol. 890, no. 1, id 13.

  16. Lu, E.T. and Hamilton, R.J., Avalanches and the distribution of solar flares, Astrophys. J. Lett., 1991, vol. 380, no. 2, pp. L89–L92.

    Article  Google Scholar 

  17. Masson, S., Antiochos, S.K., and DeVore, C.R., Escape of flare-accelerated particles in solar eruptive events, Astrophys. J., 2019, vol. 884, id 143.

  18. Miller, J.A., Cargill, P.J., and Emslie, A.G., et al., Critical issues for understanding particle acceleration in impulsive solar flares, J. Geophys. Res., 1997, vol. 102, pp. 14 631–14 660.

    Article  Google Scholar 

  19. Müller-Mellin, R., Kunow, H., Fleißner, V., et al., COSTEP—Comprehensive suprathermal and energetic particle analyser, Sol. Phys., 1995, vol. 162, nos. 1–2, pp. 483–504.

    Article  Google Scholar 

  20. Petrosyan, V., Stochastic acceleration by turbulence, Space Sci. Rev., 2012, vol. 73, nos. 1–4, pp. 535–556.

    Article  Google Scholar 

  21. Ramaty, R., Colgate, S.A., Dulk, G.A., et al., Energetic particles in solar flares, in Proc. of the 2nd SKYLAB Workshop on Solar Flares, P.A. Sturrock, Ed., 1978, chap. 4, pp. 117–185.

  22. Shih, A.Y., Lin, R.P., and Smith, D.M., RHESSI observations of the proportional acceleration of relativistics >0.3 MeV electrons and > 30 MeV protons in solar flares, Astrophys. J., 2009, vol. 698, no. 2, pp. L152–L157.

    Article  Google Scholar 

  23. Struminskii, A.B., Grogor’eva, I.Yu., Logachev, Yu.I., and Sadovskii, A.M., Solar electrons and protons in the events of September 4–10, 2017 and related phenomena, Plasma Phys. Rep., 2020, vol. 46, no. 2, pp. 176–190.

    Article  Google Scholar 

  24. Svestka, Z., The phase of particle acceleration in the flare development, Sol. Phys., 1970, vol. 13, no. 2, pp. 471–489.

    Article  Google Scholar 

  25. Temmer, M., Veronig, A.M., and Kontar, E.P., et al., Combined STEREO/RHESSI study of coronal mass ejection acceleration and particle acceleration in solar flares, Astrophys. J., 2010, vol. 712, no. 2, pp. 1410–1420.

    Article  Google Scholar 

  26. Tylka, A.J., Cohen, C.M.S., Dietrich, W.F., et al., Shock geometry, seed populations, and the origin of variable elemental composition at high energies in large gradual solar particle events, Astrophys. J., 2005, vol. 625, no. 1, pp. 424–495.

    Article  Google Scholar 

  27. Tylka, A.J., Cohen, C.M.S., Dietrich, W.F., et al., A comparative study of ion characteristics in the large gradual solar particle events of 2002 April 21 and 2002 August 24, Astrophys. J. Suppl., 2006, vol. 164, no. 2, pp. 536–551.

    Article  Google Scholar 

  28. Vlahos, L., Particle acceleration in solar flares, Sol. Phys., 1998, vol. 121, nos. 1–2, pp. 431–447.

    Google Scholar 

  29. Wild, J.P., Smerd, S.F., and Weiss, A.A., Solar bursts, Ann. Rev. Astron. Astrophys., 1963, vol. 1, pp. 291–366.

    Article  Google Scholar 

  30. Zhang, J., Dere, K.P., and Howard, R.A., et al., On the temporal relationship between coronal mass ejections and flares, Astrophys. J., 2001, vol. 559, no. 1, pp. 452–462.

    Article  Google Scholar 

Download references

ACKNOWLEDGMENTS

We thank the participants of the ground and space experiments that provided the publicly available data used in this article (GOES, RSTN, RHESSI, SOHO/EPHIN, SOHO/LASCO, and NMDB). We thank the anonymous reviewer for the careful reading of the manuscript and helpful remarks

Funding

A.B. Struminsky and A.M. Sadovskii acknowledge the support of the project Plasma 2019 and 2020. I.Yu. Grigorieva acknowledges the support of the Energy Release project. Yu.I. Logachev acknowledges the support of Russian Foundation for Basic Research (project no. 19-02-00264).

Author information

Authors and Affiliations

  1. Space Research Institute, Russian Academy of Sciences, Moscow, Russia

    A. B. Struminsky & A. M. Sadovski

  2. Institute of Nuclear Physics, Moscow State University, Moscow, Russia

    Yu. I. Logachev

  3. Central Astronomical Observatory at Pulkovo, Russian Academy of Sciences, St. Petersburg, Russia

    I. Yu. Grigorieva

Authors
  1. A. B. Struminsky
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yu. I. Logachev
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. I. Yu. Grigorieva
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. A. M. Sadovski
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to A. B. Struminsky.

Ethics declarations

The authors declare that they have no conflict of interest.

Additional information

Translated by O. Pismenov

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Struminsky, A.B., Logachev, Y.I., Grigorieva, I.Y. et al. Two Types of Gradual Events: Solar Protons and Relativistic Electrons. Geomagn. Aeron. 60, 1057–1066 (2020). https://doi.org/10.1134/S001679322008023X

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S001679322008023X

Keywords:

Search

Navigation