The Temperature Effect on Cosmic-Ray Intensity and the Height of Meson Formation

Abstract

A study has been made of the results obtained in different parts of the world for the effects of ground temperature on cosmic-ray intensity. It is found that the great discrepancies between the values for the temperature coefficient as given by different observers, as well as the seasonal change of this coefficient, far from being a difficulty in Blackett's interpretation may be taken as further evidence of the instability of the meson. The 12-monthly variation in cosmic-ray intensity as obtained by Forbush can be also accounted for as an effect of meson decay if one assumes that the bulk of the penetrating component originates at 7.5 cm. Hg pressure-level. This assumption has been put to the test and the results obtained appear to confirm that the layer of meson formation lies at, or little above, the 7.5 cm. pressure-level, at the height of the maximum of the Pfotzer curve for the intensity of the total radiation.