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Observation by an Air-Shower Array in Tibet of the Multi-TeV Cosmic-Ray Anisotropy due to Terrestrial Orbital Motion Around the Sun

M. Amenomori
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Abstract

We report on the solar diurnal variation of the galactic cosmic-ray intensity observed by the Tibet III air shower array during the period from 1999 to 2003. In the higher-energy event samples (12 TeV and 6.2 TeV), the variations are fairly consistent with the Compton-Getting anisotropy due to the terrestrial orbital motion around the sun, while the variation in the lower-energy event sample (4.0 TeV) is inconsistent with this anisotropy. This suggests an additional anisotropy superposed at the multi-TeV energies, e.g. the solar modulation effect. This is the highest-precision measurement of the Compton-Getting anisotropy ever made.

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BibTeXRIS

M. Amenomori. 2004-08-10. Observation by an Air-Shower Array in Tibet of the Multi-TeV Cosmic-Ray Anisotropy due to Terrestrial Orbital Motion Around the Sun. https://doi.org/10.1103/physrevlett.93.061101

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