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MAGEE: That is correct. For example, if you put 150 A as r Q you 

 find about one per cent recombination. You would have to change factors 

 quite a lot before you can account for the observed F reaction. The k has 

 to be an impossibly large value before there can be such a big radius. The 

 reason we liked to choose these little spheres is because it fitted in with the 

 idea of radical pair formation by a single molecule. If I say the electrons 

 are captured and H is formed away from the parent ion -- I mean at a mod- 

 erate distance -- I cannot understand why they are formed at all, because I 

 think if they had stopped at a moderate distance they would come back. It 

 is an all or none effect, I believe. They either have to come back or get 

 away entirely, as Dr. Platzman says. I would agree with him, if they can 

 get 100 A away, they may be able to go a million. That is the way it looks 

 to me. I cannot see any appreciable asymmetry. So it seems to me they 

 must be captured. 



PLATZMAN: Dr. Magee does not contend that this is going to give all 

 the fine details. This is , as far as I know, the first real attempt to get 

 kinetics out of the elementary processes. No doubt it is wrong in detail 

 along the way, but we have to get the final picture, and it can still be very 

 important even though some of the details are incorrect. 



MAGEE: I don't have a great deal more to present. I am just going to 

 say that we have taken into account the distribution of N . Actually we took 

 several trial distributions and calculated the correct ratio of G F /(Gp + Gpj) 

 for gamma rays, as I said. We decided that a test would be to calculate c 

 for tritium -p, since the average primary event spacing is more like 150 A 

 and all the reaction does not occur before the spheres start overlapping. 

 So part of the tritium-P effect is due to the isolated events, and part of it is 

 due to the overlapping of neighboring events. We calculated this using the 

 same N Q distribution and using the same constants. The ratio Gp/(Gp+Gp{) 

 turned out to be 0.32 for tritium, whereas it had been 0.23 for gammas. 



BURTON: I don't know whether it is clear to everybody what you mean. 

 What Dr. Magee means is that Ghormley and Allen (12) did some work on 

 tritium water, and the radiation was the beta emission from the tritium. It 

 is to this experimental situation that the calculation applies. 



ALLEN: He is referring to the more recent and much better work of 

 E.J. Hart (13). 



MAGEE: It is a self-irradiation of tritium water. 



GARRISON: I should like to bring up a point regarding the HOH reac- 

 tion. The total radicals observed either as H, OH, H 2 or H 2 02 should vary 

 with the specific ionization, according to this picture. 



MAGEE: Yes. 



GARRISON: But Hart found that this is not the case. 



MAGEE: I don't know of any very clear-cut results along that line. 



GARRISON: I don't think it has been completed as yet. In the work 

 he did with polonium alphas forming gases with tritium betas and cobalt 

 gammas he found that the total number of radicals observed as H, OH, H 2 

 and H 2 2 was a constant. 



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