TRAVELING-WAVE TUBES 



55 



to 



0.8 

 0.6 



0.4 

 0.3 



0.1 

 0.08 



0.06 



'^ 0.04 

 J^ 0.03 



0.01 

 0.008 



0.004 

 0.003 



r TT^ 



\ \ 



v-\ 



^ \ 

 \J, -. 



\\ 

 l\ 



vV 



\\ 

 \\ 



vV 



\\ 

 \\ 



a\ 



\\ 

 ^\ 

 \\ 



'\ 



\\ 



: vt 



A 



\ 

 A 

 \\ 

 Kc 



-S\ 



\\ 



v\ 



\\ 

 ^\^ 



\\ 

 \\ 

 \\ 



V 



. ^^^^ 



V 



] \ 



\ 

 \ 



\ 



\ 



3 4 



X 



Fig. A1.4 — The correct value of A'i(A') (solid line), <7 + In (y )[ hiX) from the 



series expansion 16 (upper dashed line), and the first term of the asymptotic series 20 

 (lower dashed line). 



