Characteristic Features of Solar Cosmic Rays in the 21st–24th Solar-Activity Cycles According to Data from Catalogs of Solar Proton Events

The anisotropic angular distribution of cosmic rays (CR) in the interplanetary medium manifests itself on Earth as periodic diurnal intensity variations. Ground-based detectors of CRs have different energy sensitivity to the primary CR radiation and, therefore, the amplitude and phase recorded by them are also different. This fact makes it possible to study the energy spectrum of the variations when using a sufficient number of detectors. In this work, the results of the investigation of the energy spectrum of solar-diurnal variations of CRs obtained by a network of neutron monitors and muon telescopes are presented. The network allows measuring CRs with median energies from units to hundreds of GeV. The expected values of the amplitude and phase of the daily CR variations at the selected ground-based stations for different types of the energy spectrum are shown. The calculated data are compared with experimental data for 19-24 solar activity cycles.

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Simulation of the modulation of galactic cosmic rays during solar activity cycles 21–23

Bulletin of the Russian Academy of Sciences Physics ◽

10.3103/s1062873807070246 ◽

2007 ◽

Vol 71 (7) ◽

pp. 974-976 ◽

Cited By ~ 7

Author(s):

A. V. Belov ◽

R. T. Gushchina ◽

V. N. Obridko ◽

B. D. Shel’ting ◽

V. G. Yanke

Keyword(s):

Solar Activity ◽

Cosmic Rays ◽

Galactic Cosmic Rays ◽

Activity Cycles ◽

Solar Activity Cycles

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About long term modulation of cosmic rays in the 23-24 solar activity cycles

NMDB@Home 2020 - Cosmic ray studies with neutron detectors ◽

10.38072/2748-3150/p3 ◽

2021 ◽

pp. 23-29

Author(s):

Anatoly V. Belov ◽

Raisa T. Gushchina ◽

Victor Yanke

Keyword(s):

Magnetic Field ◽

Solar Activity ◽

Cosmic Rays ◽

Solar Magnetic Field ◽

The Sun ◽

Model Calculations ◽

Activity Cycles ◽

The Magnetic Field ◽

Solar Activity Cycles

Recently, there has been a significant trend in magnetic fields on the Sun. The total magnetic field of the Sun from the end of the 22nd cycle of solar activity (SA) has more than halved and this decrease continues. Chan- ges in the magnetic field are the key to all the active phenomena occurring on the Sun and in the heliosphere and, accordingly, to processes in cosmic rays. In long-term CR variations in 23-24 cycles of SA the attenuation of the solar magnetic field is displayed and these variations turned out to be the smallest for the entire time of CR observations. Model calculations of CR modulation for 21-22 and 23-24 cycles of SA showed: with a slight difference in the regression characteristics obtained, the distribution of contributions to the generated CR modulation from the effects of various SA indices is strongly varies in the analyzed periods. Possible reasons for the features of the last two CA cycles are discussed.

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Stratospheric measurements of cosmic rays in the 19th–22nd solar activity cycles

Advances in Space Research ◽

10.1016/0273-1177(94)90541-x ◽

1994 ◽

Vol 14 (10) ◽

pp. 779-782 ◽

Cited By ~ 2

Author(s):

G.A. Bazilevskaya ◽

M.B. Krainev ◽

Yu.I. Stozhkov ◽

A.K. Svirzhevskaya ◽

N.S. Svirzhevsky

Keyword(s):

Solar Activity ◽

Cosmic Rays ◽

Activity Cycles ◽

Solar Activity Cycles

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COSMIC RAY FLUXES IN THE MAXIMUM PHASE OF SOLAR ACTIVITY CYCLES

International Journal of Modern Physics A ◽

10.1142/s0217751x05029757 ◽

2005 ◽

Vol 20 (29) ◽

pp. 6669-6671

Author(s):

G. A. BAZILEVSKAYA ◽

V. S. MAKHMUTOV ◽

Y. I. STOZHKOV ◽

A. K. SVIRZHEVSKAYA ◽

N. S. SVIRZHEVSKY

Keyword(s):

Solar Activity ◽

Cosmic Rays ◽

Cosmic Ray ◽

Lebedev Physical Institute ◽

Activity Maximum ◽

Cosmic Ray Intensity ◽

Cosmic Ray Modulation ◽

Wide Energy ◽

Activity Cycles ◽

Solar Activity Cycles

The homogeneous series of primary cosmic ray intensity with energy > 100 MeV is obtained in the long-term balloon measurements of charged particle fluxes performed by Lebedev Physical Institute. Supplementing these data with those of neutron monitors enables us to study the cosmic ray modulation on the wide energy base during more than four solar activity cycles. In the periods of solar activity maximum a transition from cosmic ray decrease to recovery occurs. Changes in fluxes of cosmic rays of lower energy lag behind the changes in fluxes of cosmic rays of higher energy producing an energy hysteresis. After a while cosmic ray fluxes of all energies start to recover. In the cycles 20 and 22 the periods of transition from decline to recovery were shorter than in the cycles 21 and 23. This may be indicative of more complicated passage from the cosmic ray drift in the A > 0 conditions to the drift in the A < 0 conditions than vice versa.

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