daemon@ucbvax.UUCP (07/21/84)
From @MIT-MC:JLarson.PA@Xerox.ARPA Fri Jul 20 19:23:22 1984
Arms-Discussion Digest Volume 2 : Issue 47
Today's Topics:
Soviet blast
New Kind of Nuclear Weapon?
OTA Background Paper on BMD
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Date: Tue, 17 Jul 84 15:25:49 est
From: pur-ee!Physics.els@Berkeley (Eric Strobel)
Re: Soviet blast
I wonder if anyone knows of some group (high school or college, etc.)
that routinely monitors rain water just for the heck of it. The point
being that if the rain water is checked for radioactivity, perhaps they
may have detected whether or not some nuclear weapons were involved in the
explosion at the Soviet naval base.
ERIC STROBEL
UUCP: {decvax,ucbvax,harpo,allegra,inuxc,seismo,teklabs}!pur-ee!Physics:els
INTERNET: els @ pur-phy.UUCP
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Date: 20 Jul 1984 8:41-PDT
From: dietz%USC-CSE@ECLA
Subject: A New Kind of Nuclear Weapon?
Here's an idea for a novel kind of nuclear explosive, using neither
fission nor fusion.
The idea is to find some nuclear isomer N which is (1) excited (above
the ground state), (2) has a long halflife, and (3) has above it (in
energy) another isomer N' which decays very rapidly to the ground
state. The energy difference between N' and N should be a few tens or
hundreds of electron volts.
Hitting an N nucleus with this energy difference can cause it to go to
state N', from which it decays to the ground state. Assuming that N'
is (say) 1 MeV above the ground state, one gets an energy
multiplication of on the order of 10 to 100 thousand.
The triggering energy can be delivered in any number of ways. If the
energy difference is sufficiently small, laser light will do the trick.
Higher trigger energies could be supplied by fast electrons or by
simply heating the matter to a sufficiently high temperature (100 ev is
about 780,000 degrees K). If the state N' decays by alpha emission the
decay energy will be deposited locally, hopefully propagating a chain
reaction.
The energy density of this kind of nuclear fuel will be less than that
of fission fuel (~ 200 Mev per fissioned nucleus, or ~1 MeV per
nucleon) or fusion fuel (17.6 MeV from DT fusion, or 3.5 MeV per
nucleon). Still, considerable yields are possible (after all, in the
Hiroshima bomb only about 1% of the U235 nuclei fissioned).
Nice features of this kind of explosive: (1) there's no lower limit on
bomb size (since there's no critical mass effect), (2) there's no
fission waste or neutrons produced, so the bomb could be very clean,
(3) if N' decays by alpha particle emission the bomb could be designed
with negligible prompt radiation.
Disadvantages: (1) An isomer N has to be found, (2) N has to be
manufactured, which is likely to be expensive, (3) if N decays by gamma
emission shielding will be required.
Uses for this kind of explosive: (1) neutron bombs replacements
(especially if N' emits high energy gamma rays), (2) as clean primaries
for fission-free fusion bombs, or as ultraclean bombs for peaceful
purposes, (3) for very small nuclear devices (nuclear hand grenades?).
Also, controlled induced decay could allow novel kinds of nuclear
batteries or nuclear engines (nuclear powered trucks? tanks?
airplanes?).
Where can we get N? Perhaps some isotopes in fission reactor waste fit
the bill. If not, neutron capture produces nuclear isomers;
underground fusion bomb explosions could provide the neutrons. (Could
this be a reason why the government is still doing underground "tests"?)
The Advanced Energy Projects department of DOE is funding research into
finding isomers of this kind for use in gamma ray lasers (for
laboratory use).
dietz@usc-ecla
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Date: Fri, 20 Jul 84 10:10:37 PDT
From: Leo Marcus <marcus@AEROSPACE>
Subject: OTA Background Paper on BMD
From the "Principal Judgments and Observations" section of Directed Energy
Missile Defense in Space, Office of Technology Assessment, April 1984,
OTA-BP-ISC-26:
"1. The prospect that emerging "Star Wars" technologies, when further
developed, will provide a perfect or near-perfect defense system, literally
removing from the hands of the Soviet Union the ability to do socially
mortal damage to the United States with nuclear weapons, is so remote that
it should not serve as the basis of public expectation or national policy
about ballistic missile defense (BMD)...
2. The wisdom of deploying less-than-perfect ballistic missile defenses
remains controversial...
3. The strategic goal of President Reagan's Strategic Defense Initiative
calling for emphasized BMD research -- perfect, near-perfect, or
less-than-perfect defense against ballistic missiles -- remains unclear...
4. In all cases, directed-energy weapons and other devices with the
specifications needed for boost-phase intercept of ICBMs have not yet been
built in the laboratory, much less in a form suitable for incorporation in a
complete defense system...
5. Moreover, making the technological devices perform to the needed
specifications in a controlled situation is not the crux of the technical
challenge facing designers of an effective ballistic missile defense. A
distinct challenge is to fashion from these devices a reliable defensive
architecture, taking into account vulnerability of the defense components,
susceptibility to future Soviet countermeasures, and cost relative to those
countermeasures...
6. It is clear that potent directed-energy weapons will be developed for other
military purposes, even if such weapons are never incorporated into effective
BMDs...
7. For modest defensive goals requiring less-than-perfect performance,
traditional reentry phase defense and/or more advanced mid-course defenses
might suffice...
8. Deployment of missile defenses based on new technologies is forbidden by
the ABM treaty reached at SALT I...
9. There is a close connection, not explored in this Background Paper,
between advanced BMD concepts and future anti-satellite systems."
[My comments:] Lacking from this summary, but treated briefly in the body of
the Background Paper, is discussion of the cost, both in terms of money
and stability, of an arms race in space, the problems in distinguishing
between a defensive and an offensive weapon system, and other issues which
are not purely "technological".
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[End of ARMS-D Digest]