Atmospheric temperature effects on the solar daily variation of cosmic ray intensity

Abstract

The solar diurnal variation of the cosmic ray meson intensity caused by the periodic solar heating of the atmosphere is derived from a comparison of the ionization chamber and neutron monitor data from Huancayo. The amplitude and the time of maximum are found to be 0·11% and 05–30 hr respectively. Recent meteorological data, free from appreciable radiation errors, are found to be in rough agreement with this result. Particularly good agreement is obtained in the phases which are both later than the value given by Dorman by about 4 hr. The inclusion of this temperature correction enables the directional measurements at Mawson to be reconciled with the idea of a primary anisotropy.