Modeling of the interaction of the solar wind plasma with dipolization fronts in the tail of the Earth's magnetosphere

The work is devoted to the investigation of different mechanisms of acceleration of charged particles during magnetic substorms in the tail of the Earth's magnetosphere. A numerical model is constructed that allows one to investigate the acceleration of particles of three types: electrons e-, protons H+ and oxygen ions O+ as a result of two different mechanisms: (a) a single magnetic dipole with a jump in the normal component of the magnetic field lasting several minutes; (b) multiple jumps of the normal component of the magnetic field (dipolization fronts) lasting less than a minute. It is shown that under the influence of a single magnetic dipolarization (a), a predominant acceleration of oxygen ions occurs, which increase their energies to 200 keV. In this case, protons and electrons are accelerated to a lesser extent. In comparison with the mechanism (a), the process (b) promotes a greater acceleration of protons and electrons to energies of 300 and 150 keV, respectively. Thus, the acceleration efficiency of different particle populations is resonantly related to the duration of the jump in the magnetic field. The closer the scale of the magnetic dipole field changes to the particle's gyroperiod, the more effective is their acceleration.