RADIOCHEMICAL FRACTIONATION CHARACTERISTICS 113 variations from predicted values. Particles ranging in size from 5 to 20 u were analyzed from each of two shots. Two sets of selected aggregate particles between 4 to 9 were also analyzed.’ A logarithmic fractionation correlation plot of ry49 39 VS. T95 g9* in- corporating filter-paper aggregate particles and individual particle data from both shots fitted linearly (see Fig. 3). Freiling’ has plotted ryqy 39 10? PTT = PTT TTPTyy PT OT PTT yy PT TT TTS 78 (6.9 y)O— _ }— — — a 76 (5.3 pg 62 (4-9 yp) ° | 0 75 (7.8 y) 0719 y) O77 (9 ys) 10 = 74 (13 p) - = 4 . SOLUTION 0 1 -_ = — -— 3 __ = SOLUTION os 4 ——a © SHOT A O SHOT B SOLUTION —— — yo! LLLLLL 1 Lott yeti 10 Littl 10? Po Le eiiyy 103 95,89 Fig. 3—Logarithmic fractionation correlation for 'Ba. data for megaton-range coral-surface bursts and three types of water bursts. Within the limits of error, the slope and intercept of the regression line of Fig. 3 are comparable with those of Freiling’s plot. The single particles are severely fractionated with respect to the total sample. It is interesting to note that for these particles the frac- tionation plot had to be extended another decade to include the particle r-value ratios. *r:,99 is defined as the ratio of calculated isotope (i) fissions to calculated 8Sr fissions, f;/fgs where f equals fissions. $