Safe Energy

John K Clark (
Sun, 4 May 1997 22:46:19 -0700 (PDT)


On Sun, 04 May 1997 Michael Lorrey <> Wrote:

>A breeder can be set to produce excess plutonium, produce no excess,
>or to burn up excess plutonium.

Then it's not a breeder, just a plutonium reactor.

>Getting the plutonium is one thing, but knowing how to build a bomb
>that will actually explode using only 9 pounds is another level of
>accomplishment entirely.

Making an H bomb would be tricky, but not a simple A bomb, a Physics student
working on a masters degree and a chemist with a little knowledge of
explosives could do it, if they had the Plutonium. It's really not that hard,
in fact in all the thousands of A bomb tests there has not been one dud,
it's always worked the first time.

A few years ago I had a sort of morbid curiosity about this, I figured if one
was going to blow me up one day I wanted to know something about them,
it's amazing what's available. "The Curve of Binding Energy" by John McPhee
was very useful, so was " The Las Alamos Primer" by Robert Serber and
"Mushroom" by John Aristotle Phillips. Also very interesting was a
thermonuclear weapon maintenance manual, apparently unclassified, that I
found deep in the stacks of a public library.

>it [a breeder] uses plutonium at an enrichment level of about 40%,
>half that of weapons grade.

If you're using U235 then about 80% enrichment is needed before the bomb is
practical, but if you're using Plutonium 40% would work fine, you'd need
11 kilograms of it, at 20% you'd need about 18 kilograms, at 50% you'd need
just under 10, and at 100% you'd only need 4.4 kilograms. This assumes that
the implosion is done crudely and the Plutonium is not compressed beyond its
normal density, this is never true of in modern weapons so they need less
Plutonium. The critical mass varies inversely with the square of the density
of the plutonium, but a terrorist might be too dumb to take advantage of this.
Anyway, enriching plutonium is Far easier than enriching Uranium, plutonium
is a different element so you can use chemical means.

>BUilding a bomb of the simplicity of the Nagasaki weapon requires a
>minimum of 35 pounds of plutonium,

That was over half a century ago, and far from an ideal design, for example,
the heavy tamper was placed right next to the Plutonium giving it no place
to build up speed. As Ted Taylor, the Michelangelo of A bomb designers has
publicly stated, If you want to drive a nail into a board, do you place the
hammer on the nail and then push?

>as well as requiring the use of 48 Klystron switches, which are even
>more highly controlled items than plutonium itself.

Krytrons are used in other things besides bombs, in the oil exploration
industry for example. The EGG corporation makes them, part number RN22,
cost 80$.

>WHat is a cheap and easy way to make muons?

Aim an ion beam into a target of deuterium or lithium.

John K Clark

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