Modern analytical models of electrons acceleration and propagation in solar flares
B.V. Somov Lomonosov Moscow State University, Shternberg State Astronomical Institute, Universitetskii prosp. 13, Moscow, 119889, Russian Federation
A review of the current state of the kinetic theory of acceleration and propagation of energetic (thermal and non-thermal) electrons during solar flares is presented. The classical models of a thick-target and their further development are considered in detail — models that take into account the effect of the reverse-current and the acceleration of electrons in collapsing magnetic traps. Analytical solutions of the corresponding kinetic equations are found. Based on these solutions, the characteristics of the bremsstrahlung X-ray emission generated by energetic electrons are calculated. The obtained results are compared with modern data of high-precision observations of flares. The degree of X-ray polarization is calculated, and the possibilities of measuring it in future space experiments are discussed.
Keywords: Sun, solar flare, electrons acceleration, kinetic equation, collision integral, bremsstrahlung, polarization PACS:96.60.−j, 96.60.qe, 96.60.Iv, 96.60.Tf (all) DOI:10.3367/UFNe.2021.08.039048 Citation: Gritsyk P A, Somov B V "Modern analytical models of electrons acceleration and propagation in solar flares" Phys. Usp., accepted
Received: 28th, July 2021, revised: 20th, August 2021, accepted: 27th, August 2021