The Magnetic Storm Effects and the Interplanetary Electromagnetic State

Abstract

The electric field of the beam of rarified ionised gas ejected from the sun has been invoked by Alfvén in connection with geomagnetic storms and aurorae. An attempt is made to study the effects of this electric field on cosmic rays. From a study of the ionization chamber records published by Carnegie Institution for the years 1945 and 1946, it appears that the deceleration in the electric field seems to be the most important among the types of effects expected in cosmic rays.

The study reveals that it is possible to attribute the same mechanism, namely, the beam, to explain both the 27 day variation as well as Forbush decreases. The maximum (or minimum) of cosmic ray intensity preceeds the maximum (or minimum) of Kp by about 4-6 days. The direction of the electric field of the beam is also discussed.