The solar diurnal variation of the galactic cosmic-ray intensity, observed by the Tibet III air shower array, was discussed. The variations are consistent with the Compton-Getting anisotropy in the higher-energy event samples, due to the terrestrial orbital motion around the Sun. It was found that in the lower-energy event sample, variation is inconsistent with the anisotropy. This implies an additional anisotropy, which is superposed at the multi-TeV energies, such as the solar modulation effect.
ASJC Scopus subject areas
- Physics and Astronomy(all)