H bombs

John K Clark (johnkc@well.com)
Mon, 2 Mar 1998 22:55:17 -0800 (PST)


On Mon, 2 Mar 1998 Eugene Leitl <eugene@liposome.genebee.msu.su> Wrote:

>The reflecting plane is not flat, most photons do not get reflected
>but absorbed (xRay mirror they are not)

It doesn't make much difference, if the photons are reflected the target will
receive twice the photons momentum, if it is absorbed it will still receive
the photon's momentum and its energy too.

>causing the surface material to turn into a gas cloud exploding

Right, and that will cause the inner material to implode inward and compress.

>Surface turned into gas expands into vacuum, relaxating by EM
>radiation into the environment, which, if not sol-proximal, is few-K
>(Big Bang echo) cold space.

Yes, but so what?

>You do not account for energy relaxation by radiation into

I don't understand what you're getting at, of course hot things cool off by

>Is 100 MT small enough? The difficulties we are talking about is
>hitting a flurry of habitats/mosaic of subterranous settlings
>semisimultaneously, requring a large number of brilliant warheads.

Going underground won't help much, during the gulf war bunker busting bombs
penetrated 30 feet of steel reinforced concrete to destroy installations, and
they just had chemical explosives, H bombs could do much better. I suggest
you visit the island of Elugelab, that's where the USA detonated a bomb that
was expected to be of less than 5 megatons but actually produced 15 megatons.
They blew it up in 1954 on top of a short tower, it produced a fireball 4
miles in diameter, it terrified the scientists who set it off and trapped
them in their bunker for several days on an island 10 miles away, and it
killed the Japanese sailors on the fishing boat Fukuryu Maru- The lucky
Dragon, who were far from the official danger area and well inside the
"safety" zone. Actually I'm being unfair, you can't visit Elugelab anymore,
but if you have a submarine you can look at the crater on the sea floor 250
feet deep and 6500 feet across where Elugelab once was.

>>the foam further from the fission trigger must receive weaker X rays
>>and explode with less power, this would compress the fusion cylinder
>>unevenly making a dud.

>Maybe that's why they took polymer foam instead of polymer solid,
>and adjusted the geometry accordingly to compensate for that.

Maybe, but then the design would be inefficient because if the foam was that
ephemeral then most of the X rays energy would pass through all the foam and
be wasted, it would not be available to compress the fusion cylinder. Why not
use radiation pressure?

I found a quotation that gives some support to my theory that the polymer
foam's main function was to protect vital parts made of heavy atoms for a few
extra nanoseconds, and its use as a plasma generator of only secondary
importance. Jacob Wechsler was a H bomb engineer and he's talking about
Carson Mark, the chief designer of the first H bomb:

"He was really concerned about higher Z materials [elements with higher
atomic number] being exposed. In a radiation environment with high energy
radiation coming down from the primary, anything like steel because it's
so dense will cause a pressure spike when it vaporizes. Carson was trying
to sustain a deuterium burn and he was afraid that if things blew off at
higher Z that might chop up the fuel, its temperature wouldn't stay high
enough [...] the surface of the lead would blow off so we covered the lead
with plastic, with polyethylene. That was low Z, just CH2 [hydrogen and
carbon]. From a time point of view the radiation ionization of the heavy
materials with all that shielding would be so late that it would have
zilch effect on the overall system."

>There's a reason thermonuclear devices are so difficult to build.

I wonder, are they difficult to build? Over 100,000 of the damn things have
been made and several hundred have exploded in tests, some with very unusual
designs, and yet there has not been one dud and most turned out to be more
powerful than expected.

John K Clark johnkc@well.com

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