PECULIARITIES OF SPORADIC VARIATIONS IN DENSITY AND ANISOTROPY OF GALACTIC COSMIC RAYS IN SOLAR CYCLE 24
Abstract and keywords
Abstract (English):
In this work, we have processed data from the global network of neutron monitors and muon telescopes by the global survey method to study variations in the density and anisotropy of galactic cosmic rays during Forbush decreases observed in solar cycle 24. The simultaneous use of two different type detectors made it possible to examine the temporal dynamics of the angular distribution of cosmic rays in two different energy intervals. Besides, we have used measurements of the Yakutsk cosmic ray spectrograph after A.I. Kuzmin to assess the energy spectrum index during large disturbances of the interplanetary medium in this cycle. Analysis of the results obtained confirms our early statements that solar activity cycle 24 features an increased level of turbulence in the interplanetary magnetic field.

Keywords:
cosmic rays, solar activity, Forbush decreases, energy spectra
Text
Publication text (PDF): Read Download
References

1. Alania M.V., Wawrzynczak A. Energy dependence of the rigidity spectrum of Forbush decrease of galactic cosmic ray instensity. Adv. Space Res. 2012, vol. 50, pp. 725–730.

2. Altukhov A.M., Krymsky G.F., Kuzmin A.I. The method of “global survey” for investigating cosmic ray modulation. Proc. 11th International Conference on Cosmic Rays. Budapest, 1970, vol. 4, pp. 457–460.

3. Bazilevskaya G.A., Daibog E.I., Logachev Yu.I., Vlasova N.A. Characteristic features of solar cosmic rays in the 21st–24th solar-activity cycles according to data from catalogs of solar proton events. Geomagnitism and aeronomy. 2021, vol. 61, no. 1, pp. 6–13. DOI:https://doi.org/10.1134/S0016793221010023.

4. Belov A.V., Blokh Ya.L., Dorman L.I., Eroshenko E.A., Inozemtseva O.I., Kaminer N.S. Anisotropy and time dependent changes in the spectrum of cosmic-ray intensity variations during August, 1972. Izv. AN SSSR. Ser. fiz. [Bull. Academy of Sciences of USSR. Physics]. 1974, vol. 38, pp. 1867–1875.

5. Cane H.V. Coronal mass ejections and Forbush decrease. Space Sci. Rev. 2000, vol. 93, pp. 55–77.

6. Despotashvili M.A., Nachkebia N.A., Shatashvili L.Kh. The energetic spectrum changes of Forbush effects during the different 11-year cycles of solar activity. Proc. 26th International Conference on Cosmic Rays. Salt Lake City, 1999, vol. 6, pp. 419–422.

7. Dorman L.I. Variatsii kosmicheskikh luchei i issledovanie kosmosa [Cosmic ray variations and space investigation]. Moscow. 1963, 1028 p. (In Russian).

8. Dvornikov V.M., Sdobnov V.E., Sergeev A.V. Analysis of cosmic ray pitch-angle anisotropy during the Forbush-effect in June 1972 by the method of spectrographic global survey. Proc. 18th International Conference on Cosmic Rays. Bangalore, 1983, vol. 3, pp. 249–252.

9. Gerasimova S.K., Grigoryev V.G., Krivoshapkin P.A., Skripin G.V., Starodubtsev S.A. Variation of the Forbush-decrease rigidity spectrum with the cycles of solar activity. Solar System Res. 2000, vol. 34, no. 3, pp. 262–264.

10. Gololobov P.Yu., Grigoryev V.G., Starodubtsev S.A., Zverev A.S., Gerasimova S.K. Method of global survey involving data of muon telescope network. Astroparticle Phys. 2021, vol. 131, pp. 102586. DOI:https://doi.org/10.1016/j.astropartphys.2021.102586.

11. Grigoriev V.G., Starodubtsev S.A. Temporal changes in the energy spectrum of Forbush decreases in 20–23 solar activity cycles. Bull. Russian Academy of Sciences: Physics. 2011, vol. 75, no. 6, pp. 801–804.

12. Grigoryev V.G., Starodubtsev S.A., Isakov D.D. The energy spectrum of Forbush decreases during the growth phase of solar cycle 24. Geomagnetism and Aeronomy. 2014, vol. 54, no. 3, pp. 282–286. DOI:https://doi.org/10.1134/S0016793214030062.

13. Kojima H., Shibata S., Oshima A., Hayashi Y. Rigidity dependence of Forbush decrease. Proc. 33rd International Conference on Cosmic Rays. Rio de Janeiro, 2013, 135187.

14. Krymskii G.F., Kuz’min A.I., Krivoshapkin P.A., Samsonov I.S., Skripin G.V., Transky I.A., Chirkov N.P. Kosmicheskie luchi i solnechniy veter [Cosmic Rays and Solar Wind]. Novosibirsk: Nauka Publ. [Science], 1981, 224 p. (In Russian).

15. Kuzmin A.I. Variatsii kosmicheskikh luchei i solnechnaya aktivnost [Cosmic rays variation and solar activity]. Moscow. 1968, 157 p. (In Russian).

16. Nagashima K. Three-dimensional cosmic ray anisotropy in interplanetary space. Rep. Ionosphere Space Res. 1971, vol. 25, pp. 189–211.

17. Sakakibara S., Munakata K., Nagashima K. Rigidity spectrum of Forbush decrease. Proc. 20th International Conference on Cosmic Rays. Moscow, 1987, vol. 4, pp. 67–70.

18. Shafer G.V., Kuz’min A.I., Krymskii G.F., Krivoshapkin P.A. Main characteristics of Forbush decreases during the period of minimum solar activity. Izv. AN SSSR. Ser. fiz. [Bull. Academy of Sciences of USSR. Physics]. 1967, vol. 31, no. 8. pp. 1319–1321. (In Russian).

19. Wawrzynczak A., Alania M.V. Energy dependence of the rigidity spectrum of Forbush decrease of galactic cosmic ray intensity. Proc. 32nd International Conference on Cosmic Rays. Beijing, 2011, vol. 10, pp. 288–291.

20. URL: https://www.nmdb.eu (accessed August 10, 2021).

21. URL: http://cosray.shinshu-u.ac.jp/crest/db/public/archives/gmdn.php (accessed August 10, 2021).

22. URL: https://omniweb.gsfc.nasa.gov/form/dx1.html (accessed August 10, 2021).

Login or Create
* Forgot password?