Tau

To determine Kik one should pay attention to the following circumstances: 1. Electromagnetic conditions in interplanetary space for CR propagation and modulation (which are eventually determined by anisotropic diffusion tensor Kik and by the velocity u of plasma's motion) do not remain uniform but vary in time. These variations are detailed relative to the processes on the Sun generating plasma streams, and this time delay is td ~ r/u . Let S be a factor controlling plasma outbursts from the Sun (number of solar spots, chromospheres flares, calcium flocculates etc.), then at a distance r from the Sun Kik will be

2. The kinetic energy density of plasma released by the Sun is far higher than the magnetic field related to the plasma. This relation (which holds true, according to direct measurements near the Earth's orbit) should be valid also at the larger distances from the Sun (since the kinetic energy density decreases «r-2, the magnetic energy density decreases in the same ways). Then the geometrical place of plasma portions, released from the same region of the Sun, is, according to Parker (M1963), an Archimedes spiral owing to the solar rotation with the angular frequency Q = 2n/T (T ~ 27 days is weakly dependent on the polar angle 0):

where 0s and ps are a polar angle and helio-longitude, respectively, of a plasma generation region on the solar surface. The large scale magnetic field will tend to be stretched along these spirals. Since, however, u(0s ,ps )/Q(0s) in Eq. 2.12.15 can vary considerably from region to region on the solar surface, it will result in a complicated interaction between solar plasma and magnetic field which can be a possible cause of generation of magnetic field inhomogeneities radial moving from the Sun.

3. The angle between magnetic force lines and a direction of the radial motion of magnetic inhomogeneities,

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