MEDELMA@CMS.CC.WAYNE.EDU (Michael Edelman) (11/19/90)
From: Michael Edelman <MEDELMA@CMS.CC.WAYNE.EDU>
I finally found a copy of Sam Cohen's "The Truth About The Neutron Bomb",
and as Cohen is the father of said weapon, and its greatest proselytizer,
his description might be taken as authoritative. Viz:
Let's start with a fission weapon of Hiroshima size- about 20Kt. 85% of the
energy partition is blast and heat; 10% is delayed radiation from fissile
products (the lighter parts of the split nucleii) and 5% is prompt radiation
in the form of neutrons and gamma rays.
Now, let's say we build a small fusion weapon with a minimal fission trigger
resulting in a 1Kt fission-fusion weapon. The energy partition in the fusion
reaction is 80% prompt radiation and 20% blast and heat. The result is that
this 1Kt weapon has only 0.05 the blast and heat effect of the straight
fission, but equivalent prompt radiation effects. (Recall that most weapons
in the US arsenal are fission-fusion-fission weapons, which is sort of
a way to build a much bigger fission weapon than would otherwise be possible
or practical). We also have no delayed radiation from the fusion reaction,
although there is still some from the fission trigger- though much less from
the straight 20Kt fission weapon.
Cohen's ultimate plan was to develop a pure fusion weapon with no fission
trigger. That's been mentioned in this list before, and I have absolutely
no idea if such a weapon was ever developed. However, if it *could* be develope
it would then be possible to build a 0.01Kt pure fusion device with half the
prompt radiation of the 20Kt fusion device, no delayed radiation, and blast
and heat effects of a large (20,000lb) conventional bomb. Such a device could
be detonated at a comparitively low altitude and result in no blast effects
reaching the ground while still having a kill effect from prompt radiation
over a radius of over 1000 yards.
>From this Cohen conceived his idea of a defense plan for Europe and Germany
in particular: Small, cheap bomb shelters for the populace with nothing more
than a few feet of earth as a radiation shield. The warning sounds, people
go the the shelters, the N-weapon missiles are launched, and a few hours
later the battle is over.
Cohen's book covers not only the brief technical outline of the bomb (summerize
above) but also the long political history. Highly recommended. Mine cost
me $6 in a used book store.
mike edelman medelma@cms.cc.wayne.edu medelma@waynest1