At 01:30 AM 4/9/2012, Alain Sepeda wrote:
just to quote Larsen in his cite:
- He criticize the ide that He4 is trapped, and an ad hoc excuse
- he claims that some transmutation cycle produce much more coherent
energry by He4 than DD fusion
you can fin their reasoning in
<http://www.slideshare.net/lewisglarsen/lattice-energy-llctechnical-overviewcarbon-seed-lenr-networkssept-3-2009>http://www.slideshare.net/lewisglarsen/lattice-energy-llctechnical-overviewcarbon-seed-lenr-networkssept-3-2009
page 25+
with page 34 summarizing their interpretation of McKrubre results...
they claim it works better than DD hypothesis+leak excuse.
"they claim." Once again, where is the experimental confirmation of
*their* theories?
However, let's look at this:
p.24 asks questions. If you can ask a question about an experiment
and assume there is no answer, have you discredited the experiment?
There is some "missing" helium. Given the difficulties of capturing
all the helium, the amount missing is pretty small! Further, the
"missing helium" raises the yield per He-4, it does not lower it.
After neglecting the most obvious residence of the missing helium,
they then (p.26)
give their own theory: other reactions which produce heat but not
helium. (this is stated in a confusing way, in fact, but that's the
basic point.)
Bottom line, though, the McKubre experiments described provide no
evidence for W-L theory. They merely indicate a need for further work
to tighten up the search for helium. If, after doing so, a
discrepancy remains, this again would not be evidence for W-L theory,
it would merely be evidence for *something other than deuterium ->
helium heat. How much of "something else" would depend on the exact
values found.
p. 27 reviews the McKubre result, but then criticizes it on the basis
of an alleged "belief" that cold D-D fusion was the only nuclear
reaction that could possibly take place in their experiments." No,
McKubre was pursuing helium evidence, which is the *only* solid
evidence that *significant* nuclear reactions are taking place in CF
experiments. McKubre is not nailed to a particular hypothesis of
mechanism. Some mechanism involving deuterium -> helium seems likely,
though, by Occam's Razor. This is consistently stated by
Krivit/Larsen as "d-d fusion," when there are other possibilities.
It is obvious that experimental evidence regarding other isotopic
anomalies in CF cells would always be desirable, but what Larsen's
explanation doesn't tell you is that one looks for helium with a mass
spectrometer, or techniques, that can discriminate between the mass
of D2+ and He-4+m and that mass spectrometer may not be useful at
higher Z. Bottom line, Larsen is here simply finding some level of
incompleteness in McKubre's work, and attempting to discredit the
obvious conclusions from that work on this basis. He is not reporting
evidence for his own theory.
Larsen correctly reports that gas-phase cells are being compared with
electrolytic cells, and that it is improper to assume that the
location of reaction helium would be the same. However, it is one of
the operating assumptions of CF research that the heat effect in
palladium deuteride is being produced by the same mechanism. That is
a useful assumption, to a degree. It also could easily be incorrect.
There may be many mechanisms. Occam's Razor, however, suggests not
starting there. One mystery is enough for today, tomorrow, if we
haven't solved the one mystery, we might consider that there is more
than one. However, cf the old story about the blind men examining an
elephant, each reporting something different. There is no way for the
blind men to tell, initially, if this is one object or many.
Then they get to some meat, slide 30,
According to W-L theory of LENRs, He-4 atoms should be produced on
or very near the surface of of Pd. If that were true, given the He-4
solubility is very low, why would He-4 go deeply into the Pd metal
when it is much easier for He atoms to simply enter D2 gas?
There is an obvious answer, so he gives it, next page. He proposes
that the He-4 is produced by decay of Be-8. This, in fact, is similar
to Takahashi's theory. Larsen assumes a ground state decay, which is,
in fact, one of the unresolved problems of Takahashi's theory.
(Because the Be-8 would be formed with an excitation of almost 47.6
MeV, how is this energy dumped if not in the kinetic energy of decay
products. The half-life of Be-8 is extremely short, would it have
time to transfer the nuclear axcitation energy? Not known, really.)
The ground state decay gives 46 KeV alphas, or so. Larsen shows a
penetration depth of only a few microns, for these, as if this is
enough to discredit the burial hypothesis.
*However,* if the helium is born on the surface, with some kinetic
energy, half of the alphas will have a trajectory that is toward the
palladium bulk, and will implant. Low solubiliity of helium in
palladium would mean that the helium cannot easily move through the
lattice, even a micron of palladium could be enough to prevent such movement.
Larsen's analysis of what will happen with shallowly-implanted helium
is speculative and unconvincing. Further, all this does is to *raise*
the possible Q, not lower it. Larsen ignores evidence that helium is
found in CF cathodes, within 25 microns of the surface. He places
extreme reliance on Gozzi's finding of no helium in the cathode.
Turning to his own theory, Larsen, slide 34, suggests that his theory
predicts 31.2 MeV/He-4. However, this is sleight-of-hand. Remember,
Larsen is claiming that there are many other reactions. The evolved
heat will be the sum of all the reactions. Larsen's prediction would
be based on an assumption that only reactions leading to He-4 were
occurring, when, in fact, these reactions would be relatively rare
under his theory.
He refers to slide 11, which shows a set of complex reaction series.
I have nowhere seen Larsen discuss the most serious problem with his
theory: the *reaction rate*. The rate at which neutrons are produced
must be low, or else we'd see far higher heat. Since the rate is low,
the probability of a reaction taking more than one step must be way, way low.
The analysis on slide 34 is preposterous! This is Larsen making up
reasons to support his theory, and doing a poor job of it. His theory
does *not* predict heat/helium of 31.2 MeV/He-4. I don't see, in
fact, where his theory makes a prediction of overall heat and
isotopic distributions.
Notice the concept of "cycles" being used. Cycles require a very high
reaction rate, or each step in the cycle is followed by ... nothing.
We would have to postulate that transformed atoms become highly
"attractive" to neutrons, so that they are activated at far higher
rates than the initial activation.
Larsen is correct that heat/helium hasn't been nailed down. But that
is not evidence for W-L theory, it is merely deficiency in evidence
for a theory that the major fuel is deuterium and the major ash is
helium. Where is the evidence for W-L theory? Where are the confirmed
predictions?
W-L theory allows for a farrago of proposed reactions, so one can
pick and choose for a large and complex field, to find a reaction
that might explain a particular result. And that the required
reaction series might be way-silly-improbable is ignored.
Essentially, there will be, if W-L theory of neutron formation is
correct, there will be N neutrons being formed. It is proposed that
these have a very high absorption rate, so N transmutations will be
caused. But this is N/T, where T is the total number of possible
targets. (Roughly.) A transmuted element becomes just another target,
and would presumably be exposed to the same neutron flux. The
probability of a second reaction in the "cycle" would be the square
of N/T. That would be, for all intents and purposes, close to zero.
The intermediate product would be left.
If neutrons are being created in significant numbers, we would expect
to see specific results that are not observed, and gammas are only
one aspect of this.
Looking through some of the other slides, what Larsen is doing is
searching through experimental records, finding anomalies that W-L
theory *might* explain. There is an absence of quantitative analysis.
There is an absence of clear experimental prediction. This is pure
ad-hoc speculation, and all it can do, scientifically, is to suggest
avenues for exploration. I don't see that even post-hoc analysis has
been done, adequate to suggest W-L theory as being likely.
Further, the whole structure depends on this concept: that the "heavy
electron" patch is 100% efficient at capturing all the radiation
generated by the complex reactions proposed. That should be easy to
experimentally demonstrate. Where is this work? It is key to
verifying W-L theory. Has the gamma absorption hypothesis been
tested? What about all that beta radiation, with high energies? None
would escape? Where is a quantitative analysis of isotopic production
rate to be expected from a particular surface neutron generation
rate, and a particular surface composition, compared with observed
production rates?
No, this slide show is designed to impress the unwary. It fails to
answer the serious objections raised about W-L theory, and doesn't
even seem to recognize that they exist.
