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From: chidsey@smoke.brl.mil (Irving Chidsey)
Newsgroups: sci.military
Subject: Re: Electromagnetic pulse from conventional explosives
Message-ID: <1991Jan24.035558.22167@cbnews.att.com>
Date: 24 Jan 91 03:55:58 GMT
References: <1991Jan21.035412.3674@cbnews.att.com>
Sender: military@cbnews.att.com (William B. Thacker)
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
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From: Irving Chidsey <chidsey@smoke.brl.mil>

In article <1991Jan21.035412.3674@cbnews.att.com> gsnow@pro-freedom.cts.com (System Administrator) writes:
<
<Typically you will find that the amount of EMP is directly relational to the
<size of the blast.
<
<If you have enough TNT to equal the blast potenial of a nuclear explosion,
<you would get the same amount of EMP that you would get with the same size
<nuclear explosion.  As far as I know, it has little to do with the radiation
<involved, is it just the side-effect of such a large explosion.
<
<Gary
<---


	No, moving the atoms and molecules isn't enough, because they are
electricly neutral.  The gamma rays strip the outer layer of electrons
from the atoms, about simultaneusly, and send them off at relativistic
velocities.  There is a large charge separation, and a very strong electric
field.  The nucleii are strongly attracted by the fleeing electrons, and
vice versa, and the electrons eventualy come back and electrical neutrality
is restored.  In the meantime there is one humongous electrical pulse.  At
low altitudes the density is high, averything happens at very short range,
and there just isn't enough charge separation to do anything.  You need
to strip the electrons, so conventional explosives won't do it; it takes
a nuclear bang at high altitude.

	They discovered it when they tried to find out why so many street
lights in Hawaii went out during an atomic bomb test.

								Irv

References?  Assorted ancient Scientific American articles and very old
physics texts.
-- 
I do not have signature authority.  I am not authorized to sign anything.
I am not authorized to commit the BRL, the DOA, the DOD, or the US Government
to anything, not even by implication.
			Irving L. Chidsey  <chidsey@brl.mil>