NetNews Usenet Archive 1992 #16/NN_1992_16.iso/spool/sci/physics/fusion/1882

Internet Message Format | 1992-07-29 | 3.6 KB

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From: [e-mail] (Jim Carr)
Newsgroups: sci.physics.fusion
Subject: Re: D+D:Mother of all discoveries
Message-ID: <[e-mail]>
Date: 29 Jul 92 20:29:39 GMT
References: <[e-mail]>
Sender: [e-mail]
Reply-To: [e-mail] (Jim Carr)
Organization: SCRI, Florida State University
Lines: 55

In article <[e-mail]> [e-mail] (Paul Karol) writes:
>
>It's been several days since I asked for a brief explanation of what the
>D + D --> He + gamma scheme is all about.  I got two responses.  One was
>a request that if I got any responses, please forward a copy.  The other
>was a statement that it's a crock and why was I wasting my curiosity (my
>paraphrasing).

I have been too busy to formulate a complete reply, so I was hoping to
see one and spare me the effort.  At the risk of being incomplete ....

d+d has three fusion paths: He-3 + n, H-3 + p, and He-4 + gamma.

The branching ratios are basically 0.5, 0.5, tiny (I do not recall the
value for the gamma branch, but many orders of magnitude down because
of selection rules) so no one expects to see the gamma branch.  If it
is there, it is easy to identify because there is not much background
for 20+ MeV photons.  It has been looked for and not seen.

Ying describes something that *is* stimulated emission cast in a funny
(non-standard, but clear) language.  The idea is that the presence of
either the gamma or the He-4 (or both) would stimulate the emission by
enhancing the probability for the reaction.  As I speculated and someone
here worked out, unreasonably high radiation levels are required for this
to occur according to the rules of stimulated emission.  Further, the
energy should come out in observable -- and dangerous -- radiation.

A problem for this picture is that Ying used a gamma source that produces
low energy gammas; not gammas of the same energy as the ones he wished
to stimulate, as the theory requires.  He did use an alpha source that
might produce alphas of a reasonable energy in the apparatus, but the
intensity would still be low compared to what the theory requires.  (This
is the theory that lasers are built from, so it is pretty well understood
by that experimental/technological community.)  His apparent health
argues against his own claims.

Thus his model is not wrong, but seems implausible as an explanation until
one can see some products other than heat.  If there is stimulated emission
of gammas, he should be able to detect gammas in proportion to heat!  If he
can do so, this would be a major breakthrough.  Lacking them, one is forced
back into the old problem of how to couple the fusion reaction to thermal
energy without radiation (the Hagelstein-like phonon lasers) and how to
detect He-4 products in the presence of background He-4 -- and where are
the X-rays from recoiling He-4 nuclei?  These pictures do not seem to
require stimulated emission of gammas, but their study would be helped
if one had an experiment that worked on demand.

For me, the key is whether it is a perfectly reproducible, heat-producing
experimental protocol.  If so, then one can proceed to study it.

--
J. A. Carr                                    |  "The New Frontier of which I
[e-mail]                           |  speak is not a set of promises
Florida State University  B-186               |  -- it is a set of challenges."
Supercomputer Computations Research Institute |   John F. Kennedy (15 July 60)