Dynamical features of short-period variations of cosmic rays.
Abstract
The modulation of cosmic rays by large-amplitude acoustic waves is studied by analyzing a pronounced Forbush decrease recorded September 4 through 5, 1972. The decrease was accompanied by the appearance of strong shock waves in the interplanetary medium. The characteristics of variations with periods ranging from several hours to fractions of an hour were studied on the basis of a correlation analysis and by calculating the power spectrum from the cross-correlation function of two pairs of diversity-reception stations. It is shown that low-amplitude variations with periods of 24, 9, 6, 4 hours and 80, 30, 17, and 12 min reflect the state of the interplanetary medium for relatively quiet conditions, whereas large-amplitude variations with periods of 7 hours and 40 to 45 min carry information on transient processes occurring in this medium.
- Publication:
-
Akademiia Nauk SSSR Izvestiia Seriia Fizicheskaia
- Pub Date:
- September 1974
- Bibcode:
- 1974IzSSR..38.1908K
- Keywords:
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- Cosmic Rays;
- Dynamic Characteristics;
- Periodic Variations;
- Shock Wave Interaction;
- Sound Waves;
- Earth Magnetosphere;
- Magnetoacoustic Waves;
- Power Spectra;
- Radiant Flux Density;
- Velocity Modulation;
- Space Radiation