The Deflection of Cosmic-Ray Charged Particles in Passing Through Magnetized Iron

Experiments are described in which the deflections suffered by cosmic-ray electrons in passing through the saturated iron core of an electromagnet are detected by means of Geiger counters. The observed effects are compared with the results of calculations in which we have used the energy distribution as found by Anderson and Neddermeyer with the cloud chamber. In this way we have found it possible to set limits to the effective magnetic vector within the iron. One of our experiments indicates a value lying between the induction $B$ and $\frac{B}{2}$. The other points to the limits $\frac{3B}{4}$ and $\frac{B}{4}$. A theoretical discussion is included in which it is pointed out that all electrons of the same energy will not necessarily experience the same deflection but will show a statistical distribution of deflections with an arithmetic average corresponding to the induction $B$. The present type of experiment, however, does not give a true arithmetic average and would be expected to indicate, for the effective deflecting vector, a quantity less than $B$ to an extent dependent upon the particular geometrical arrangement.