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.
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