A. S. Kovtyukh

Influence of the charge exchange and coulomb collisions on proton pitch angle distributions form in the Earth's radiation belts

Radial evolution of the proton pitch angle distributions at L<5.25 for 0.03<E<10.0 MeV is considered for various models of the radial diffusion (with various correlation between coefficients of the magnetic and electric diffusion and various dependencies of these coefficients on geomagnetic latitude) and selected spacial distributions of the neutral exosphere atoms and cold plasma of the plamasphere. The results of the numerical simulation are compared with experimental data. It is shown that the best agreement of numerical models with experimental data is achieved using for the numerical simulation radial diffusion coefficients that are independent of geomagnetic latitude, given by DE = 5 × 10−6 L10(L4 + μ2) and DM = 5 × 10−9 L10RE2day−1.

Numerical simulation of proton pitch angle distribution in the real magnetosphere of the Earth

Abstract A new method of numerical simulation of the proton pitch angle distribution (PAD) based on Liouvilles theorem is presented. It yields good results for that region of the Earths magnetosphere where the transport rate far exceeds the loss processes (charge exchange and Coulomb collisions) rate. Obtained numerical models of the proton PAD are in good agreement with the experimental data and explain all features of the PAD of proton fluxes with energy E > 50 keV experimentally measured in the Earths magnetosphere at 3 R / R E R E is Earths radius) and different MLT (magnetic local time) during geomagnetically quiet periods.

Dynamics and ions composition of the ring current during substorms: the Gorizont‐35 results

The geosynchronous satellite Gorizont‐35 observations and analysis of the ring current H+ (protons), He2+ (α‐particles) and O+ ions energy spectra variations near noon (11.30±01.30 LT) and midnight (23.30±01.30 LT) during substorms and storms (11–25 March 1992) are presented. Measurements were made in the energy range E=41–133 keV/e in seven channels (ΔE/E≊0.1). It has been discovered that the O+ ions are the main component of the ring current energy density during the period of the active Sun. The He2+ ions are the most dynamic component of the ring current (especially for E<70 keV/e). At midnight the H+, He2+ and O+ ions energy spectra are similar to the same energy per charge presentation form. The obtained data are compared with the AMPTE/CCE(CHEM) results. Formation of the space and energy features mentioned above and variations of ring current ions composition physical processes are discussed.

Variations of the multi-component ring current energy spectra during the geomagnetic storms: “Gorizont-35” results

The geosynchronous satellite Gorizont-35 results of observations and analysis of the ring current H+, He2+ and O+ ions energy spectra variations near midnight (23.30±01.30 LT) during substorms and storms 11–24 Mach 1992 are presented. Measurements were made in E=41 – 133 keV/e energy range in seven channals (ΔEE≈0.1). It was found that the O+ ions are the main component of the ring current energy density during the period of the active Sun. The He2+ ions is the most dynamic component of the ring current (especially for E<70 keV/e). The H+, He2+ and O+ ions energy spectra are almost similar in the same energy per charge presentation form.