Atmospheric effects on the hard component of cosmic radiation near sea level

Abstract

Atmospheric effects on the hard component of cosmic radiation were studied at Lincoln. Nebraska (51° N geomagnetic latitude; 350 m altitude) with narrow- and wide-angle Geiger-counter telescopes (20 cm Pb absorber). Intensity measurements were made from 1 Sept, 1953 through 16 Feb. 1956, and linear regression analyses were carried out for several possible combinations of atmospheric variables and the cosmic-ray intensity. A detailed comparison is made of the results obtained from triple-regression calculations based upon the 50 mb, 100 mb and 200 mb Duperier models and the Olbert model. It is found that the 50 mb Duperier model is superior to all others tested, but the extent to which the intensity can be corrected by statistical methods is limited at present by the accuracy of the radiosonde data. Experimental results are in good general agreement with those of other investigators and agree well with the theoretical predictions of Trefall with regard to the temperature effect. They are in poor agreement with the predictions of Trefall on the barometric effect, however, and do not substantiate the theoretical conclusions of Olbert. The smoothing of the intensity curves seems to be practically indifferent to the terms employed in the regression equation if it involves three or more atmospheric variables.