-particle is expelled, the group of the resultant body is
unit greater than that of the parent.
As will be seen this is exactly what is to be expected according to the considerations of [§4].
In escaping from the nucleus, the
-rays may be expected to collide with the bound electrons in the inner rings. This will give rise to an emission of a characteristic radiation of the same type as the characteristic Röntgen radiation emitted from elements of lower atomic weight by impact of cathode-rays. The assumption that the emission of
-rays is due to collisions of