is the flux density of CR with all energies.

The Eq. 2.16.3 has the form of the continuity equation with a source on the right-hand side the sign of which determines just the character of the variations of energy density of CR. As results from Eq. 2.16.3, a sign of the term, corresponding to the source in the case of radial outflow of solar wind plasma, is determined of a direction of the radial gradient of CR and with the positive gradient of CR (taking place for galactic CR) this term represents the amount of energy which is accumulated by particles in unit volume per unit time-interval in their interaction with moving inhomogeneities of the magnetic field. Thus, the total number of particles in this case is conserved, according to Eq. 2.16.6, and the energy density of particles is increased; it is the typical situation for the presence of a process of particle acceleration. If the radial gradient of CR is negative, the inverse process takes place, i.e. particles transfer their energy to inhomogeneities of the magnetic field and are decelerated. The same conclusion concerning the character of energy exchange between CR and moving inhomogeneities of magnetic field results from the Eq. 2.16.1. The Eq. 2.16.1 is an equation of Fokker-Plank type, and to estimate the physical meaning of the terms in this equation, one should write it in the canonical form, i.e. in the form of conservation of particle number in phase space:

p t) + divJ (r, p, t) + div _J_ (r, p, t) = 0 , (2.16.9)

dt where Jp (r, p, t) is the flux density of particles in the momentum space and the subscript index p of the operator divp implies that in the case under consideration one should take into account only the part of divergence operator in the momentum space which depends on the absolute value of the momentum. Including Eq. 2.16.9 we write Eq. 2.16.1 in the form t) + dr {- a (r, p, t^ + Dap dp jn(r, p, t)


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