The modulation of galactic cosmic ray intensity in the small anisotropy approximation
Heading:
| Fedorov, YI, Shakhov, BO, Kolesnyk, YL |
| Kinemat. fiz. nebesnyh tel (Online) 2022, 38(4):3-16 |
| https://doi.org/10.15407/kfnt2022.04.003 |
| Start Page: Space Physics |
| Language: Ukrainian |
Abstract: The cosmic ray propagation in the interplanetary medium is investigated on the base of transport equation. The solution of the cosmic ray transport equation is obtained under known energetic distribution of charged energetic particles on the heliosphere boundary. The galactic cosmic ray spectrum in the local interstellar medium is taken on the base of data obtained by Voyager 1 and Voyager 2 spacecrafts. The galactic cosmic ray flux in various solar activity periods is calculated. The estimates of cosmic ray intensity gradients are made and comparison of these calculations with space missions data are fulfilled. The calculations of the cosmic ray angular distribution anisotropy are made. It is shown that galactic cosmic ray flux at the Earth orbit has an azimuthally direction and the anisotropy value of protons with energies from 1 MeV to 1 GeV roughly corresponds to 0.5 %. |
| Keywords: cosmic rays, heliospheric magnetic field, transport equation |
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