246) Manipulating nuclear decay rates


Ludwik Kowalski (8/7/05)
Department of Mathematical Sciences
Montclair State University, Upper Montclair, NJ, 07043

Introduction:
The major controversy of cold fusion is whether or not nuclear processes can be influenced by processes taking place at the atomic and molecular level. The prevailing view, based on reproducible experimental data, is that what happens in atomic nuclei (containing at least 4 protons) cannot be influenced by chemical changes. The half life of ¹³⁷Cs, for example, is the same in chemically pure cesium, in all compounds of cesium, in atoms located in air, in the vacuum, in digestive systems of living organisms, or in sources located near crystal screens. It is probably the same for strongly ionized cesium atoms in our sun and other stars. That point of view has been challenged when the discovery of cold fusion was announced in 1989. According to Fleischmann and Pons, nuclear processes of some kind can be triggered by chemical processes taking place in some electrolytic cells. Other cases, contradicting the prevailing view, have been reported since that time. Two such cases are described below.

Microbial destruction of a radioactive cesium
Members of the International Society of Condensed Matter Nuclear Science (ISCMNS) now have a restricted Internet discussion list named CMNS. At the 11th International Conference on Cold Fusion (ICCF11, September 2004) a Ukrainian scientist, V.I. Vysotskii, presented a paper on microbial decomposition of radioactive cesium. This morning I referred to that paper in a reply to a message from another member. I wrote:

Thanks for the second message about the BT (bacterial transmutations). I have some questions and comments.

1) How do recognized authorities in microbiology react to BT reports? Do they dismiss them as pseudoscience or do they take them seriously?

2) I suspect that most of us here are not competent enough to either validate or criticize experiments to which you refer. One has to know the metabolism of various living organisms and be a good analytical chemist.

3) I had some difficulties with what you wrote; probably because I am neither a biologist nor chemist. For example, in one place you write: “With the germinating wheat he reported [Hg] -200%; for oats [Hg] -2000%, [Zr] -700%, [Pd] -300%; both were analyzed by ICP-MS.” How to interpret such percentages? What is ICP? Should I assume that MS stands for a mass spectrometer?

4) In the reply to your first message I referred to the ICCF11 paper of V. Vysotskii et al. He reported that radioactive Cs-137 (half-life of about 30 years) can be turned into something non-radioactive in several days. Most CMNS subscribers are probably aware that rapid deactivation of Cs-137 and Sr-90 would simplify radioactive waste disposal problems (dealing with spent reactor fuel rods) by at least one order of magnitude. Many objections against nuclear electricity would no longer be valid.

5) Vysotskii report on bacterial decomposition of Cs-137 is listed in our <www.lenr-canr.org> library. Unfortunate, unlike his other ICCF11 report, it is not downloadable. Was it published in a biological journal? The paper was based on experiments which many physicists (working with biologists) can perform by using a widely available NaI gamma spectrometer. The microbial transmutation would be recognized as real if radioactivity was destroyed rather than transferred, for example as a metabolically produced gas escaping a culture flask. Another potential error would be to ignore a drastic redistribution of Cs within the flask (leading to a very significant change in counting geometry). V. Vysotskii, who supervised the biological experiments, seems to be fully aware of such potential traps. I was highly impressed by precautions taken by the team to avoid trivial errors.

If my memory can be trusted they had about ten identical experiments (and ten controls) occurring at the same time? Rapid decrease of radioactivity (in days instead of 30 years) was observed in each tube. That was about one year ago. What is the situation today?

6) Suppose you find a microbiologist willing to replicate Vysotskii's experiment. The first question would be "where do I get the Cs-137?" A science supplies catalog for teachers will show you where a Cs-137 source of ~ 1 microcuries can be ordered. No license is needed for a source of such activity. Other option is to use dry wild mushrooms. Let me tell you a story about this.

7) More that ten years ago a biology teacher from my university visited his family in Poland and brought back dried mushrooms. Knowing about Chernobyl I suggested that we put about 200 grams of them next the NaI spectrometer. The peak at 660 keV became clearly recognizable after about one or two minutes. But we wanted to be sure that this was due to Chernobyl. So we obtained similar mushrooms gathered in the USA and repeated the experiment. To our surprise we discovered the same 660 keV peak, but the activity (per gram of dry mushrooms) was about 3 times lower. Cs-137, mostly from nuclear explosions in 1960's, is all over the world. Our findings were published in a biological journal. Wild mushrooms are likely to be a good source of Cs-137 for your experiments.

Nobody responded to my reply, so far. This, however, does not surprises me, people who I expected to comment might be on vacation at this time of the year. I will append good comments, if they materialize. Please revisit this unit next month.

A sheet of mica near a radioactive source changes the gamma decay probability
A year before announcing the microbial effect on ¹³⁷Cs, Vysotskii and his colleagues (from Moscow State University) made another announcement. That was at the 10th International Conference on Cold Fusion (ICCF10, August 2003). Their paper, entitled “The theory and experimental investigation of controlled spontaneous conversion nuclear decay of radioactive isotopes,” can be downloaded from the library at <www.lenr-canr.org>. Let me summarize the experimental part of that interesting paper.

A radioactive source -- ⁵⁷Co -- (T=257 days decaying into ⁵⁷Fe by K-capture) -- was placed in front of a detector. Gamma rays of energies of 136.4 keV, 122 keV and 14.4 keV, emitted from the ⁵⁷Fe nuclei (T=1 nsec) were recorded. There is nothing new about this; the energy diagram of the decay process is shown below.

Unfortunately, no bars of errors were assigned to individual data points and nothing was stated about reproducibility of results. For example, is R always equal to 0.82 when X=250 microns? And is R always equal to 0.88 when X=420 microns? I will assume that observations were reproducible and that the error bars were “too small to be shown.” To give the authors all benefits of my doubt, I will also assume that control experiments were performed to show that equivalent screens made from other materials had negligible effect on the values of R at different X.

Taking these assumptions for granted I tentatively accept the main claim of the paper: “In these experiments we discovered an inhibition of the conversion channel for nuclear decay by 7–10%, and a change (increase) of the total lifetime for the radioactive ⁵⁷Fe* isotope by 6–9%, at the optimal size X of the slot, in relation to spontaneous decay in free space without the thin mica crystal.”

P.S.
This mica screening effect on ⁵⁷Fe is not as strong as the bacterial effect on ¹³⁷Cs. But each of these effects, if confirmed by other researchers, will show that the prevailing point of view has only a limited validity. Emission of gamma rays is a nuclear effect and ability of influencing it by screening the source with a thin sheet of mica (a mono-crystal) is not consistent with the prevailing point of view. How can a crystal, situated hundreds of microns from the atomic nuclei of the source influence what happens in the nuclei? To answer this question one should be able to understand the theoretical part of the paper. Unfortunately, i do not understand it, due to my very limited background in theoretical physics. But I would very much like to know what theoretical physicists think about the paper. By skimming the first part of the paper I notice that the explanation is based, among other things, on the concept of “zero-energy.” The authors claim that experimental results confirm their theory.

Why tracers have not been used to study transmutations? (Appended on 8/8/05)
Focusing on transmutations involving radioactive isotopes has a great advantage over focusing on stable isotopes. Most people here are well aware that analytical techniques used to study stable isotopes are much less sensitive than analytical techniques used to study radioactive substances. Let me illustrate this numerically. I will arbitrarily assume that the limit of detectibiity, of cesium, by a traditional analytical method is one microgram. This is 4.5*10¹⁵ atoms. Yes, I know that the limit is different for different elements; this is probably a good representative number. Let me compare it with the limit of detectivity of ¹³⁷Cs, for example, in mushrooms. Suppose I am using an NaI crystal in a situation in which a 660 keV peak can easily be identified when the corresponding counting rate is 1 per second. I will assume that the counting efficiency, including the geometry, is 1%. It means that I am able to easily recognize ¹³⁷Cs in a source whose activity is 100 disintegrations per second.

How many atoms are there in that source? The half-live of 30 years implies that the decay constant, lambda, is equal to 6.75*10^-10 sec^-1. If the activity is 100 then the number of atoms is 1.48*10¹¹. That is about 30,000 times less of the above-chosen level of detectibility by a non-nuclear analytical method. I selected cesium because bacterial transmutation of that material is being studied in Ukraine. And I have no doubt that even 10¹⁰ atoms of ¹³⁷Cs can be identified with a carefully designed high efficiency detection system.

If I were to study nuclear transmutations involving non-radioactive elements I would think about using tracing techniques. Suppose generation, or destruction, of common ¹³³Cs is suspected in the electrolyte of a Naudin’s “reactor.” How can this be tested? By deliberately injecting a tiny amount of radioactive ¹³⁷Cs, perhaps a fraction of a milligram, into the liquid before the experiment. The rest should be obvious to a nuclear scientist.

a) Take several cc of the fresh electrolyte and dry it to create a spot source. Then measure the radioactivity, A1, of that source.

b) Conduct the experiment.

c) Take several cc of the used electrolyteand dry it to create another spot source. Then measure the radioactivity, A2, of that source, under identical conditions.

If A1 and A2 turn out to be significantly different then you have an indication that the suspected transmutation might have occurred. Note that only the ratio is needed, systematic errors in A1 and A2 are likely to be identical and they should cancel each other when the ratio is calculated. That is only a general idea. Reality is likely to be less simple. Fortunately, practical difficulties can usually be resolved by anticipating various complicating factors. One should be certain, for example, that a difference between A1 and A2 is not due to the redistribution of cesium, say from the liquid to a metal, or to the surrounding air, during the experiment. Designing a convincing experiment is always a challenge.

To study transmutations involving silver the radioactive tracer could be the beta and gamma radioactive ¹¹⁰Ag (T=253 days). To study transmutations involving zinc the tag could by ⁶⁵Zn (T=245 days), to study transmutations of platinum the tag could be ¹⁸⁸Pt (T=10 days), etc. Shorter half-lives are better, in principle, because they offer higher sensitivities. On the other hand, working with a rapidly decaying tracer would call for corrections based on duration of experiments. A radioactive tracer whose half-life is about ten times longer than the duration of an experiment seems to be ideal, provided its activity can easily be measured, with an available detector, at reasonably high efficiency. Yes, I know that obtaining necessary tracers can be a problem, unless one has access to an experimental nuclear reactor, or to beams of accelerated particles.
P.S.
This note has been inspired by G. Milley's ICCF10 review of transmutations. His paper is downloadable from our library at <www.lenr-canr.org>.