Thanks for enlightening me. I knew someone during the Manhatten project DID push two subcritical masses together and got some very interesting result and died shortly afterward.
You explaination made alot of sense
Thanks
That was Louis Slotin. Searching on his name will bring up a memorial site, and other information. There have been other criticality accidents, most recently the one in Japan with the accidental mixing of larger-than-intended quantities of liquid solutions containing fissile materials (not good because there is moderator in there as well as fissile forms).
There was a near-miss safe geometry incident at the Portsmouth GDP in this country some time ago because of a plugged feed line which was a result of oil intrusion into the process stream. What avoided criticality in that case was the lack of a reflector. When they cut the plugged section out of the line the forklift operator set it on the floor. Bad move, because concrete (and the soil below it) can reflect neutrons. Fortunately, the assembly never attained criticality.