Sun's shadow by 10 TeV cosmic rays under the influence of solar activity

Abstract We examined the Sun's shadow by 10 TeV cosmic rays observed with the Tibet air shower array during the period from 1991 through 1997. The results suggest that there is a causal relation between the shadow's movement and the changing inclination of the heliospheric current sheet of the large-scale solar magnetic field. Thus, further observations with higher statistics may provide direct information on the relation between a time variation of the large-scale structure of the solar and interplanetary magnetic fields and the phase of solar activity cycle.