548 BELL SYSTEM TECHNICAL JOURNAL 



For large values of r(/->10), these reduce to 



_ l+*'cos9 cos 29 ^ .^ 

 J=—7^ 2 — ' ''>10- 



(38) 



In view of the somewhat complicated character of the function in 

 the range l/4^r^5 the curves shown below have been computed. 



These show J = P+iQ as a function of r for 9 = 0, |-, ^, y, ^. By 



interpolation it is possible to estimate with fair accuracy the value 

 of the functions for intermediate values of 9. 



Fig. 2 P = realpartof 



