Irkutsk, Russian Federation
employee from 01.01.1999 until now
Irkutsk, Irkutsk region, Russian Federation
Irkutsk, Russian Federation
UDK 53 Физика
We study the 27-day cosmic-ray (CR) intensity variation occurring in November–December 2014, using ground-based measurements from the worldwide network of neutron monitors and GOES-15 satellites. A determining factor in the considerable difference between amplitudes of the 27-day CR variation in November–December 2014 is shown to be significant changes in energy losses taking place when particles move in regular heliospheric electromagnetic fields. In this period, there was a long-living corotating trap produced by a vast coronal hole in the south of the Sun in interplanetary space. Configuration of this trap induced the energy loss of ~3–20 GeV CRs, due to which ground-based neutron monitors recorded an abnormally large amplitude of the 27-day variation.
cosmic-ray modulation, solar activity, 27-day variations
1. Dorman L.I. Variatsii kosmicheskikh luchei I issledovanie kosmosa [Cosmic ray: variations and space exploration] Moscow, AN SSSR Publ., 1963. 1028 p.
2. Dvornikov V.M., Sdobnov V.E. Variations in the rigidity spectrum and anisotropy of cosmic rays at the period of Forbush effect on 12-15 July. Intern. J. Geomagn. Aeron. 2002, vol. 3, no. 3, p. 217.
3. Dvornikov V.M., Sdobnov V.E., Sergeev A.V. Analysis of cosmic ray pitch-angle anisotropy during the June 1972 Forbush effect by method of spectrografic global survey. Proc. 18th ICRC. Bangalore. India. 1983, vol. 3, p. 249.
4. Dvornikov V.M., Kravtsova M.V., Sdobnov V.E. Diagnostics of electromagnetic characteristics of the interplanetary medium based on cosmic ray effects. Geomagnetism and Aero- nomy. 2013, vol. 53, iss. 4, pp. 430-440.
5. Gil A., Alania M.V. Energy spectrum of the recurrent variation of galactic cosmic rays during the solar minimum of cycles 23/24. Solar Phys. 2016, vol. 291, iss. 6, pp. 1877-1886. DOI: 10.1007/ s11207-016-0924-z.
6. Gil A., Mursula K. Exceptionally strong variation of galactic cosmic ray intensity at solar rotation period after the maximum of solar cycle 24. Proc. the 34th International Cosmic Ray Conference, 30 July - 6 August, 2015, The Hague, The Netherlands. PoS(ICRC2015)149.
7. Krymsky G.F. Modulyatsiya kosmicheskijh luchei v mezhplanetnom prostranstve [Cosmic ray modulation in the interplanetary medium]. Moscow, Nauka, 1969, 152 p.
8. Lee C.O., Luhmann J.G., de Pater I., Mason G.M., Haggerty D., Richardson I.G., Cane H.V.,·Jian L.K., Russell C.T., Desai M.I. Organization of energetic particles by the solarwind structure during the declining to minimum phase of solar cycle 23. Solar Phys. 2010, vol. 263, iss. 1-2, pp. 239-261. DOI:https://doi.org/10.1007/s11207-010-9556-x.
9. Modzelewska R., Alania M.V. The 27-day cosmic ray intensity variations during solar minimum 23/24. Solar Phys. 2013, vol. 286, iss. 2, pp. 593-607. DOI:https://doi.org/10.1007/s11207-013-0261-4.
10. URL: http://www.solarmonitor.org (accessed September 8, 2018).
11. URL: http://wso.stanford.edu (accessed September 8, 2018).
12. URL: http://satdat.ngdc.noaa.gov./sem/goes/data/new_avg (accessed September 8, 2018).
13. URL: https://omniweb.gsfc.nasa.gov/ow.html (accessed September 8, 2018).
