Shape of the Beta-Ray Distribution Curve of Radium E at High Energies

Abstract

The beta-ray spectrum of radium E was measured by means of a magnetic spectrometer and coincident counters with special emphasis on the shape of the curve in the neighborhood of the end-point. Because of the strong source available, and the low background of the detecting mechanism, it was possible to obtain significant data much closer to the end-point than has been done heretofore. The distribution was found to end, without a tail, at Hp = 5330 oerstedcm, or 1.17 X10 6 electron volts. The Fermi and K-U plots of the experimental data do not give straight lines as predicted by the theory. Extrapolation of the straight part of the K-U plot gives an end-point 17 percent higher than that observed.

The Nuclear Isomers ofIn116

“…It is interesting to note that, although in some cases the K-U extrapolated end points are considerably higher than those obtained by inspection, 8 in the present case they appear to agree with the end points obtained by inspection to about 0.1 Mev. From all the data it seems that the best values for the end points are: for the 13 second period, 3.1 ±0.1 Mev; for the 54 minute period 1.4±0.1 Mev.…”

Application of semiclassical methods to reaction rate theory

“…39 One first constructs a model or comparison equation This method is ideally suited for the treatment of tunneling because the solution of an inverted parabolic barrier is known, and hence one can compare the exact potential to the parabolic barrier in order to obtain the .connection formula between the solutions across the barrier. 39 The result is, (see, e.g., Ref. 28) (1.9)…”

Wrong for the Right Reasons

“…The wrong theory had been compared to the experimental results. Similar cautions concerning this type of comparison had been made earlier by Langer and Whittaker (1937) and by Paxton (1937). Langer and Whittaker noted that "The K-U plot was made without considering the fact that radium E is a forbidden transition.…”