标题:The influence of the sidereal cosmic-ray anisotropies originated on the tail- and nose-boundaries of the heliomagnetosphere (HMS) upon the solar cosmic-ray anisotropy produced inside the HMS
摘要:The solar diurnal variation of cosmic rays was considered to be fully explained by the diffusion-convection
theory. Recently, however, it has been found that the geographic latitude distribution of the yearly averaged
diurnal variations observed with the neutron monitors and the muon telescopes on the ground does not agree with
that expected from the theory. The difference between the two distributions is observed almost every year, and
it is especially remarkable in the solar activity minimum period in the positive polarity state of the solar polar
magnetic field, when the diurnal variation reduces its magnitude and shifts its phase towards the morning side. It
is shown that such a difference is produced by the seasonal variation of the sidereal heliotail-in and helionose-in anisotropies with respective right ascensions of 6 h and 18 h according to the following process. Generally, if
any sidereal anisotropy from the right ascension α is subject to the seasonal variation with its maximum and
minimum at the times when the Earth is closest to and farthest from the source of the anisotropy, respectively,
located through its direction at the boundary of the HMS, it produces a yearly averaged residual flux from 0 h LT
in solar geographic polar coordinates regardless of its direction (α). This residual flux from 0 h LT produces the difference mentioned above.
关键词:Cosmic rays (CR) ;solar and sidereal anisotropies of CR ;solar modulation of CR ;seasonal variation of CR sidereal anisotropy ;neutron monitors ;polarity of solar magnetic field ;heliomagnetosphere (HMS) ;CR acceleration on HMS boundary ;major axis of HMS