was bee-busy making plutonium and its byproducts ... Could we go to war with a single atom bomb?” Even so, Dr. Mackenzie’s revelation meant that the U.S. was no longer the only nation in ...

For example, each atom of the Pu-238 isotope contains 144 neutrons ... Next, the nuclear reaction products were chemically separated by means of the plutonium-uranium extraction (PUREX) process. First ...

As each uranium atom breaks apart, it shoots out neutrons ... in a rare form of uranium (U-235)—or converted into plutonium (Pu-239). Heavy water can play a role in breeding weapons-grade ...

After helping to engineer the plutonium bomb that was dropped on Nagasaki ... a maximum size beyond which an atom won’t be stable even fleetingly, as a sort of chemical mayfly.