The study of artificial radioactive isotopes is at the present time one of the most important topics in nuclear research. It involves the establishment of a detailed term scheme for the disintegration in question. Not only are the energies of the components of the different beta and gamma radiations of interest, but also their intensities. These data give information concerning the probabilities of transitions between the different nuclear energy levels. From them it is possible to draw conclusions regarding the mechanism of the disintegration and to correlate the spina and parities of the levels.

The general method of controlling the radio frequency for the full scale Bevatron will be the same as that used on the 1/4 scale machine. The details of course will be modified to meet the requirements of greater range, higher output voltage and closer tracking tolerances. In addition, there is the added complication introduced by the current ripple.

The electrostatically deflected beam of the 184-inch cyclotron has been used with the stacked foil and absorber technique to determine the excitation functions. The data are presented graphically and discussed individually for each of the reactions. The results are discussed in terms of compound nucleus formation, transparency effects, and other factors in order to arrive at a qualitative picture for the mechanism of high energy nuclear reactions with heavy nuclei.