365) A shot-in-the-dark CR-39 experiment

Ludwik Kowalski; 5/12/2009
Department of Mathematical Sciences
Montclair State University, Upper Montclair, NJ, 07043

Several weeks ago I observed an interesting classroom demonstration by a colleague, Professor Robert Dorner, for students at Montclair State University. He charged a 0.6 mF capacitor to 300 volts and discharged it through a thin aluminum foil placed on a table. The foil disintegrated instantly producing an intense flash of light  and a gun-shot-like noise. This reminded me of a report by Lochak and Urutskoev (1). These researchers also discharged a capacitor through a thin foil. But their 0.27 mF capacitor was charged to 6000 and discharged through a thin titanium foil placed in a tube of water, inside a hermetically sealed chamber.

L&U reported that the explosion changed the isotopic composition of titanium. The relative abundance of Ti-48, after the explosion in water, was found to be 5% lower than it was before the explosion. The decrease in the relative abundance of Ti-48 was not accompanied by a relative increase in the relative abundance of any other titanium isotope. Presumably, the missing fraction of Ti-48 isotope was transformed into another element, or elements. A change in the isotopic composition of an element would be an undeniable signature of a nuclear process. This observation, first reported in (2), was independently confirmed by another team of Russian researchers (3).

Nuclear processes are often accompanied by emission of nuclear projectiles, such as neutrons, protons and alpha particles. Is it possible that a detectable number of such projectiles is emitted when Dorner’s capacitor is discharged? The experiment described below was performed (together with Robert Dorner) to answer this question. Our setup is shown in Figures 1 and 2. Cables are connected to the charged capacitor and the left titanium piece is pushed toward the right stationary titanium piece. This results in an electric arc of very short duration, below the CR-39 chip. The distance between the right titanium tip and the CR-39 chip was  only several millimeters. That is much less than the range of a typical alpha particle in air. Nuclear projectiles, if they were emitted, would be intercepted by the CR-39 and would produce detectable tracks.

Our experiment differed from that of U&L’s in several way. We were not attempting to study chemical and isotopic compositions; we used what we have to obtain a clear yes-or-no answer to a simple question--are detectable nuclear projectiles emitted from the arc region? Presence of such particles would show that, contrary to the prevailing opinion, nuclear processes can result from atomic processes, such as electric arc discharge.

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Etching and observing background tracks
All CR-39 chips were etched together in a 6.5 M NaOH solution for five hours and inspected under the microscope. Then the chips were etched for additional seven hours. The temperature of the etching solution was 66 C. Short preliminary etching was necessary to observe elliptical pits, if any. I know that such pits (tracks) become circular after long etching, as illustrated in Figures 4 and 5 in


The elliptical pits seen after 5 hours of etching were oriented randomly. No specifically oriented elliptical tracks were found in this experiment; missing them would be a loss of significant information. Additional seven hours of etching made pits larger, as illustrated in Figure 3. Counting of larger pits is easier than counting of smaller pits.

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Figure 3:
Right picture shows pits due to alpha particles from Am-241, after 5 hours of etching. Each diameter is close to 8 microns. Left picture shows pits (each diameter is close to 28 microns) on a background chip, after 12 hours of etching. Sizes of photographed areas are 260 by 200 microns, under magnification of 200.

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Note that photos in Figure 3 show areas of 260 by 190 microns while the photos in Figure 4 show areas of 1310 by 960 microns. The two photos in Figure 4 show an example of background tracks.

Tracks of nuclear particles are always present on CR-39 surfaces. They are due to alpha radioactive substances, usually radon, present in our environment. The track density on the surface facing the arc (see Figure 1) turned out to be larger than the track density on the opposite side. But is the difference significant? To answer this question I examined surfaces of several CR-39 chips that were not exposed to the arc. These chips were cut from the factory-protected sheet at the same time and were handled in the same way as the experimental detector. The results are shown in the table below. The mean for the last column is 55.4 while standard deviation is 17.2

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Figure 4
Two photos of size 1310 by 960 microns (magnification 40) from the same surface of a background chip. The left photo shows the high pit concentration area; the right photo shows the low pits concentration area. These two areas are only about 0.3 mm away from each other.

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The mean track density is about three times larger than it was about two years ago. I will return to this topic in the next paragraph. Let me first mention something that might be significant in the context of SPAWAR experiments. In his Catania presentation Lipson et al. speculated that copious SPAWAR pits might be due to an electrical (rather than nuclear) effect. He exposed CR-39 chips to plasma and observed pits similar to those created near the SPAWAR cathode.  My unprotected chip was only 7 mm away from the center of an electric arc plasma. On that basis I expected to see copious "ground beef" pits (that is how Russian scientists referred to copious pits in Catania) on the surface of my experimental chip. Absence of such pits, on the CR-39 surface that was facing the arc, might be significant.

Pit densities on different background chip surfaces (column 4 in the table below) fluctuate between 25 and 87. That seemed to be strange; all chips were cut from the same ship and were handled in the same way (same long exposure time to air). Then I realized that local densities, on individual surfaces, also fluctuated widely, as illustrated in Figure 4. I suspect that electrostatic charges, somehow deposited on CR-39 surfaces, attract radioactive ions floating in the air. Under this hypothesis, the non-uniform distribution of pits corresponds to the non-uniform distribution of static electric charges. How else can the non-uniformity of pit distribution, on the same surface, be explained? If that hypothesis is correct, then the number of tracks on a chip surface depends on a factor which is not under my control. Fluctuations of mean densities for different surfaces (column 4 in the table below) is probably also due to uncontrollable static charges.
  Chip label   Area(cm^2)   # of pits   (pits/cm^2)

A (scratched) 1.5 78 52
A (opposite) 1.5 69 46
X(scratched) 1.65 42 25
X(opposite) 1.65 63 38
D(scratched) 1.9 144 76
D(opposite) 1.9 90 47
G(scratched) 1.5 119 79
G(opposite) 1.5 80 53
E(scratched) 1.4 122 87
E(opposite) 1.4 66 47
Delta (scratched) 1.65 84 51
Delta (opposite) 1.65 130 78
T(scratched) 1.3 73 56
T(opposite) 1.3 60 46
PI(scratched) 1.2 48 40
PI(opposite) 1.2 79 66
It is clear to me now that the mean background and standard deviations would be lower if the following decision were not made. Anticipating the possibility of positive results I wanted to have an experimental proof that the titanium used was not contaminated with an alpha radioactive substance, such as radium or uranium. One of the chips was placed on the surface of titanium for 41 days. All other chips were cut at the same time, and kept in the same corner of the room for the same amount of time. That was a monumental mistake. Testing for titanium should have been delayed; it would have been necessary only after discovering a positive effect.

The following additional experiment was conducted to verify that the prolong exposure of chips to air was indeed responsible for a large fraction of background. Four CR-39 chips were cut from the same sheet and etched several hours later. The mean density of pits (from eight surfaces) turned out to be 28 (instead of 55) and standard deviation turned out to be 8 (instead of 17).

Plasma exposure results
But not all is lost; high and uncertain background would not prevent me from discovering a nuclear activity producing pit densities of the order of several hundred pits/cm2. At least I know that such activity was not present. Three experiments were performed, two with titanium tips, as illustrated in Figure 1, and one with an exploding palladium foil.

Chip III, used with titanium, was “protected” with a six-micron mylar film. That film was burned during the explosion. The area of the chip was 2.2 cm2. The number of tracks found on the side facing the explosion was 110. This translates into an average density of 50 pits/cm2. This is not different form the mean background density.

Chip VI, used in another experiment with titanium, was “protected” by two layers of six-micron mylar film. That double protection was also burned during the explosion. The area of that chip was 2.7 cm2. The number of tracks found on the side facing the explosion was 99. This translates into an average density of 37 pits/cm2. This is also consistent with the expected background.

The titanium, from which my pieces were cut, was said to be 99.9% pure; it was provided by “Titanium Fabrication Corporation.” Scraps of 99.9% pure Alfa Aesar palladium foil (0.1mm), were provided by Rick Cantwell.

a) The following is attributed to Ernest Rutherford: “If your experiment needs statistics, you ought to have done a better experiment .”

b) Unlike other CMNS experiments in which I participated, this one was not an attempt to replicate reported results. I had no reason to expect excessive nuclear CR-39 tracks in electrical explosions at 300 volts. But I enjoyed the self-imposed, intuition-motivated task of finding the tracks.

c) No evidence of copious pits, similar to those reported by SPAWAR researchers, was found on CR-39 chips exposed to an electric arc. In fact, no evidence any excessive pits was found during this shot-in-the-dark experiment.

Another monumental mistake was discovered. I confused two CR-39 sheets. Instead of cutting chips from the sheet purchased about two years ago (sharing the cost with Oriani), I cut them from the older sheet (sent to me by Scott Little, about five years ago). Here are comparisons of backgrounds:

Five years old sheet: mean background 28; standard deviation 8

Two years old sheet: mean background 13; standard deviation 4

In both cases chips were etched shortly after being cut (exposure to air was less than one hour, exposure to salty water was about ten hours). Salty water is a conductor used to remove static charges, if any.

I also measured thickness of the blue coating protecting the sheets. They 11 mg/cm^2. Experimental results I reported at Catania were obtained by using the two-year-old CR-39 material. Oriani probably also used this better CR-39 in recent experiments.

Appended on 6/7/2009
The following problem was solved--to back my claim that observing practically no tracks on one viewing area and more than ten tracks in the adjacent area (which I obeserved several times). Ten particles are randomly distributed between two identical boxes. Eleven outcomes are possible. One of them is zero particles in box A and ten in box B. The other, more probable outcome is 1 in box A and 9 in box B, etc. The most probable outcome should be 5 in A and 5 in B. Probabilities of these outcomes are shown below. They were obtained from a Monte Carlo simulation of ten millions random throws.

Probability=0.00098 for 0 and 10
Probability=0.00970 for 1 and 9
Probability=0.04402 for 2 and 8
Probability=0.11727 for 3 and 7
Probability=0.20514 for 4 and 6
Probability=0.24608 for 5 and 5
Probability=0.20481 for 6 and 4
Probability=0.11733 for 7 and 3
Probability=0.04395 for 8 and 2
Probability=0.00972 for 9 and 1
Probability=0.00099 for 10 and 0

(1) Georges Lochak and Leonid Urutskoev; “Low-Energy Nuclear Reactions and Leptonic Monopole, Proceedings of the 11th International Conference on Cold Fusion, 2004,” edited by Jean-Paul Biberian, published by World Scientific Publishing Co. Pte. Ltd, 2006. (also  http://www.lenr-canr.org/acrobat/LochakGlowenergyn.pdf )

(2) L.I. Urutskoev, V.I. Liksonov, and V.G. Tsinoev, “Observation of Transformation of Chemical Elements During an Electric Discharge,” Ann Foun. L. de Brogle 27 701, (2003).

(3) V. D. Kuznetsov, G.V. Mishinski, F.M. Penkov, V.I. Arbuzov, and V.I. Zhemnik, “Low Energy transmutations of Atomic Nuclei of Chemical Elements,” Ann Foun. L. de Brogle 28 (2), 173-213 (2003).