Physics of auroral phenomena : proceedings of the 33rd Annual seminar, Apatity, 02 - 05 March, 2010 / [ed.: A.G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2011. - 206 с. : ил.

Strengthening effect o f the magneticfield due to the precipitation o fchargedparticles Results Equation (2) is solved numerically using the model of the magnetic field [5]. In this model, the magnitude o f the current in the tail of the magnetosphere depends on the interplanetary magnetic field (IMF) and solar wind pressure. For the case prior to dipolarization we are taking the value component of the IMF Bz =- lOnT, after depolarization Bz =- 5nT, By = 0 for both cases. Pressure of the solar wind accepts 2nPa. Pressure in the plasma layer at colatitude 0 = 30° prior and after depolarization was specified as lOnPa. The distribution of Bz component o f the magnetic field in the magnetosphere is shown in fig.l (1) before and after dipolarization (2), J?E-radius o f the Earth. In fig.2 the distribution of the plasma pressure is shown. The strengthening of the Bz magnetic field component occurs simultaneously with the decrease o f the plasma pressure p. Fig. 1. The distribution of Bz component of the magnetic field in the magnetosphere before (1) and after dipolarization (2). 0.25 0.2 CO ti <u «0-15 or > a. § CO 0.1 ADIABATIC PROCESS X=-9.7RE X — 8RE ' '•У X=-8.6RE 2 X—7.4RE ! ■'/- «ft Fig.2. The distribution of the plasma pressure before (1) and after dipolarization (2). 26.5 26.9 27 26.6 26.7 26.8 Colat(degree) Fig. 3. The distributions of the kinetic energy of charged particles in magnetic flux tubes vs colatitude в before (1) and after dipolarization (2). In fig.3 the distributions of the kinetic energy of charged particles in magnetic flux tubes 3/2 p V versus colatitude в before (1) and after dipolarization (2) have been shown, it allows to determine changes of these quantities in the magnetic flux tubes. The fig. shows that the value of the kinetic energy of charged particles decreases significantly after dipolarization. The same fig. shows the value o f the kinetic energy o f particles in the magnetic flux tubes in the case of an adiabatic process. Let us appreciate the cooling tubes o f the magnetic field due to the precipitation o f the particles. The current in the arcs of the aurora can reach values o f 10 A/km2, the average energy of injected particles will take as 5 keV. The time of depolarization is 5 minutes. Then the amount of heat lost by a magnetic tube with a single magnetic flux is equal to 0.055 R e (J/ Wb). This value is sufficient to explain the cooling of the magnetic flux tubes at distances of up to 10 47