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BELL SYSTEM TECHNICAL JOURNAL 



hand portion of this curve is simply traced from Fig. 5, with a horizontal 

 shift suflicient to give an intercept at i' = 0.3; the right-hand portion was 

 constructed by placing the paper for Fig. 7 over that for Fig. 5, shifting 

 horizontally until the point corresponding to one of the values of 5 marked 

 on Fig. 5 lay on the axis of ordinates of Fig. 7, marking the position of the 

 point labeled with one plus this value of s, and repeating. 



0.4 



4 = 



Eo/^hT" 



Fig. 7 — Variation of hole density nn with distance x at time t = t assuming nh\ = 0.3 «o 

 recombination rate = nhnt/rno, and neglecting diCfusion. 



Figure 8 shows sample plots of v against 5 for the same case of ideal 

 volume recombination, with vi = 0.3, for ^ = 0.5 and ^ = 1.0. Curves for 

 a different vx would start out exactly the same, but rise higher. The rising 

 portion of the curve for ^ = 0.5, for example, was constructed from the 

 curve of Fig. 5a by locating various points (^, v) on the latter curve and 

 associating with the v value of each such point a value of 5 equal to the 

 difference of the 5 values marked on the curve of Fig. 5a for the two points 

 abscissae ^ and (^ — 0.5). As Fig. 5a was prepared entirely by slide rule, 

 the accuracy is not all that can be desired; the individual computed points 

 are shown to give an idea of the magnitude of the computational errors. 



