DISCOVERY OF THE NEUTRINO — COWAN 



Nuclear Explosive 



Expec+ed Fireball 

 from Explosion 



419 



/ / / y y /"////// / y / / / / 



Back Fill 



Suspended Detector — ^5* 



Vacuum Tank" 



SCHEME FOR DETECTING NEUTRINOS 

 FROM A NUCLEAR EXPLOSION 



Buried Signal Line for 

 Triggering Release 



/ / / y \/ y / 



Vacuum Pump 



Vacuum Line 



:-->> 4— Feathers and Foam Rubber 



Figure 4 



you think that physicists are not superstitious, just ask one about the 

 number 137 sometime. He'll be evasive and say, "Oh, you mean 1/137, 

 the fine structure constant." Press him to explain it, however, and 

 you'll see what I mean.) We arranged for the drilling of a hole and 

 the taking of cores at the nuclear test site in Nevada to explore the 

 underground conditions there. Arrangements also were made to 

 measure ground shocks and neutron backgrounds at various depths in 

 the hole during forthcoming nuclear explosions so that we could plan 

 more specifically. Our group began work on the problems of light 

 transmission over long paths in the scintillator liquids, the operation of 

 large banks of photomultiplier tubes, and the design of the great 

 vacuum tank and its release mechanism. 



But then we stopped the work suddenly, for a better idea had 

 occurred to us. 



PROJECT POLTERGEIST — II 



It was a late evening in the fall of 1952. Eeines and I had addressed 

 a seminar of the Laboratory's Physics Division that afternoon, de- 

 scribing the progress of the work and our latest plans. At the end. Dr. 

 J. M. B. Kellogg, Chairman of the Division, had suggested that we re- 



