1. The first results were given inNuovo Cimento,15, 500 (1960).
2. R. R. Wilson:Nucl. Instr.,1, 101 (1957).
3. L. I. Schiff:Phys. Rev.,70, 87 (1946).
4. E. Janke andF. Emde:Tables of Functions (New York, 1945).
5. G. Bologna, G. Diambrini, A. S. Figuera, U. Pellegrini, B. Rispoli, A. Serra andR. Toschi: Internal note no. 17 of Laboratori Nazionali di Frascati (Sept. 28, 1959) to be published inNucl. Instr. and Methods.