ppy to sell out. Within a
week, the land, the building, and other possessions of the school--including 1,600 books
Los Alamos, or "the Hill," as it was commonly referred to, officially opened for
All bombs, and especially those being developed at Los Alamos, release energy in
A certain amount of energy, called the binding energy, is required to hold the
nucleus of an atom together. This energy is relatively small for light elements and steadily
increases for heavier elements as far as cobalt, iron, and nickel. After that, in still heavier
elements, it begins to decrease to the point that the binding energy of an extremely heavy
atom, such as uranium, is less than that of many, much lighter elements.
A small portion of the mass of each particle is lost when it enters a nucleus so that
a proton, for instance, actually weighs less inside the nucleus than outside. It must do this
to fit in. To do this, it converts some of its mass into energy. The combined mass loss of
all the particles of the nucleus equals the binding energy.
There are two processes by which particles can be made to lose weight. One,
called fission (the type of bombs dropped on Japan), happens when a heavy nucleus splits
apart into two lighter nuclei. These newly formed nuclei have a higher binding energy
than their heavier "parent" nucleus; therefore, they demand a further weight loss on the
part of their particles. The other process, called fusion, occurs when two light nuclei fuse
together to form a single heavier nucleus with a higher binding energy. In both cases the
particles must lose mass and release energy. Certain types of atoms with many protons
and neutrons in their nucleus are radioactive; they are unstable and may break apart
spontaneously. Other types, upon absorbing neutrons, break apart. In this process, the
entire nucleus falls apart into two pieces, releasing energy in the...