Investigation on the cosmic-ray shadow of planets and asteroids

The moon shadow and sun shadow of cosmic rays are commonly used to calibrate the angular resolution of the instrument in extensive air shower experiments, measure the proton-antiproton ratio, and study the interplanetary magnetic field (IMF). The shadow effect of planets and asteroids in the solar system, on the other hand, has received little attention. If considerable shadow effects can be observed, a novel approach may be developed to calibrate the point spread function and investigate the IMF. In this work, we calculate the sensitivity of observing the shadow effects of planets and asteroids in the next hundred years using LHAASO’s instrumental response as an example. The result shows that the blocking impact of these celestial bodies is minimal; thus, their influence on the direction distribution of cosmic rays is negligible.