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BELL SYSTEM TECHNICAL JOURNAL 



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Fig. 13.5 — The .v's and y's for the three forward waves when the circuit field is purely 

 transverse at the thin electron stream, for zero magnetic focusing field (/^ = 0). 



1.0 

 0.5 



Fig. 13.6 — Curves similar to those of Fig. 13.5 for a parameter /' = 1. The parameter 

 / is proportional to the strength of the magnetic focusing field. 



