A New Type of Artificial β-Radioactivity

THE energy spectrum of positive electrons from magnesium, when bombarded by α-particles of radium C' reduced in range to 6.3 cm., were investigated by a method already described¹. It was found that the number of positives is less than that expected from the measurements of the integral effect. Changing the direction of the magnetic field, a great number of negative electrons could be observed. The number of negative electrons was about four times as great as the number of positive electrons.