Excess radiation at the Pfotzer maximum during geophysical disturbances

Observations of the counting rate of a single Geiger counter at the Pfotzer maximum (∼50 gm/cm2 atmospheric depth), when compared with nucleonic intensity data obtained with a sea-level neutron monitor, indicate the temporary presence of radiation in excess of. normal cosmic radiation during geophysical disturbances at a latitude well below the auroral zone. In the absence of such disturbances, the total intensity variations at the intensity maximum were found to be 2.2 times larger than variations of the nucleonic intensity at sea level.