User:MigFP/2004 DoE panel on cold fusion

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In 2004, the US Department of Energy (DoE) set up a panel of 18 scientists to review the status of cold fusion research. It was asked 3 questions: "is the evidence of cold fusion convincing?", "is the evidence convincing beyond doubt?", and "should research continue?". It was divided on the first one, mostly negative for the second one, and nearly unanimously positive for the third one.

Contents 1 History 2 Summary of the document presented by the researchers 2.1 Excess heat 2.2 Nuclear ashes 2.3 Other nuclear effects 2.4 Conclusions 3 Main conclusions of the review by the panelists 4 Reviewer comments 5 Sources 6 Notes 7 Further reading

[edit] History

In late 2003, a group of cold fusion researchers requested the DoE to review the new experimental data and supporting theory since the 1989 review. DoE accepted, and asked the requesters to prepare a review document that identified the most significant experimental observations and publications, and those areas where additional work would appear to be warranted. In July 2004, this document was submitted to the DoE by Professor Peter Hagelstein of MIT, Dr. Michael McKubre of SRI International, Professor David Nagel of George Washington University, Dr. Talbot Chubb of Research Systems Inc., and Mr. Randall Hekman of Hekman Industries.

The Basic Energy Sciences and Nuclear Physics Offices in the DOE Office of Science conducted a peer review of the submitted material in a manner typical for a DOE sponsored university or laboratory research program. The review had two components. First, the review document received by DOE was sent out for peer review by mail. Nine scientists with appropriate scientific backgrounds in experimental and theoretical nuclear physics, material science, and electrochemistry were identified by DOE, and were given approximately one month to review the report and supplementary material. The second part of the review consisted of a one-day review conducted on August 23, 2004. The reviewers consisted of nine additional scientists chosen by DOE for their expertise in relevant fields. The known reviewers are Allen Bard (University of Texas), W. Brown (Lehigh University), M.Y Chou (Georgia Tech), W. Coblenz (DARPA), G. Hale (LANL), K. Kempar (Florida State University), D. Klepner (MIT), D. Liebenberg (Clemson University), B. Mueller (Duke University), P. Paul (BNL), J. Smith (formerly DoE).^[1]

Anonymous comments from the mail peer review referred to above were provided to members of the reviewers prior to the presentations. Oral presentations were made to the reviewers by research scientists, chosen by the authors of the review document. Six research groups gave approximately one hour presentations on the work being performed in their laboratories: Peter Hagelstein (a MIT physicist), Graham Hubler (a Navy researcher) and four other scientists from Russia (Andrei Lipson), Italy (Vittorio Violante) and the United States (Steve Jones, Michael McKubre, Ed Storms).^[2] The meeting began with harsh questions, but at the end of the day, the mood had visibly lifted and the researchers and panelists shook hands.^[3] Individual comments from reviewers were requested following the presentations. The choice to collect individual conclusions rather than elicit a group recommendation allowed the DOE to close the meeting to the public under a loophole of federal law.^[4]

The organisation of the panel has been criticized both by cold fusion researchers and skeptics. Some skeptics complained that the names of the reviewers were not published^[5], and that it circumvented the Federal Advisory Committee Act ^[6]. CMNS researchers say that the DOE review was limited in scope, by request of the DOE.^[7] Thus nuclear transmutations and other topics were not reviewed. Furthermore, the reviewers were not active in the fields, did not know of its key experiments and were ignorant of its literature.. Their detailed responses showed lack of interest and had serious flaws in their justification.

[edit] Summary of the document presented by the researchers

In the document submitted to the DOE, the researchers did not address the entire body of research. Instead, they presented a subset of research from two areas: selected issues associated with excess heat production in deuterated metals, and a brief discussion of some aspects of nuclear emissions from deuterated metals.

[edit] Excess heat

Excess heat has been observed with a variety of calorimeters based on varying operating principles and by different groups in different labs, with the experiments detailed in this report reflecting similar results. The authors state that possibility of calorimetric errors has been carefully considered, studied, tested and ultimately rejected.

In 1989, Fleischann and Pons used an open cell from which energy was lost in a variety of ways, and the differential equation used to determine excess energy was awkward and subject to misunderstanding, and has an accuracy of 1% or less. Experiments at SRI International use a flow calorimeter around closed cells. The governing equations in the SRI experiment become trivial, and have accuracy of 0.5 % or better. Successful experiments show excess power well above the accuracy of measurement.

The excess heat effect has its origin within the metal deuteride, as shown by measurement of temperature gradients in the electrolyte. It is not yet clear whether the excess heat is a surface or bulk effect. The energy density relative to the total cathode volume is measured at 450 eV/atom and above, a value much greater than what might be expected from chemical effects.

The effect appears to increase approximately parabolically with the level of the D:Pd atomic ratio in the cathode, above a threshold of D:Pd of about 0.875. Below that threshold of loading, no effect is observed; above 0.95, all 49 experiments at SRI International in 1990 and 1991 manifested excess heat well above measurement uncertainty. Such high loading is accompanied by high internal pressure, and it is necessary for the cathode to be able to withstand it. Even in high loading conditions, the deuterons are further apart than in D₂, so that the pair-wise fusion rate cannot promote an excess heat effect.

The excess heat effect seems to be correlated with the surface chemical potential of deuterium, although inhomogeneous loading, important deuterium fluxes and contamination by other species such as lithium make its measurement imprecise. The excess heat effect also increases with temperature, resulting in a thermal positive feedback effect. The temperature dependence follows the Arrhenius equation, with an activation energy of about 15 Kcal/mol. This small activation energy is thought to be associated with creating the proper chemical environment and not associated directly with the nuclear process. Excess power also increases linearly with the electrochemical current density, above a threshold of about 265 mA / cm ².

The excess heat effect is often observed to be stimulated by changes in the experimental conditions, such as the application of a heat pulse, changes in current density. Quantitative evidence indicates that deuterium flux plays an important role in triggering the excess heat effect.

[edit] Nuclear ashes

There are insufficient chemical reaction products to account for the excess heat by several orders of magnitude. The attention has been directed to the search for nuclear ashes in amounts commensurate with the energy produced. Searches for neutrons and other energetic emissions commensurate with excess heat have uniformly produced null results. Although there appears to be evidence of transmutations and isotope shifts near the cathode surface in some experiments, it is generally accepted that these anomalies are not the ash associated with the primary excess heat effect. The focus of attention has been on helium as the primary nuclear reaction product.

Three independent studies have shown that the rate of helium production measured in the gas stream varies linearly with excess power. Extensive precautions were taken to ensure that the samples were not contaminated by helium from the earth's atmosphere (5.2 ppm). Bursts of excess energy were time-correlated with bursts of ⁴He in the gas stream. However, the amount of helium in the gas stream was about half of what would be expected for a heat source of the type D + D -> ⁴He. It is thus believed that helium is partially retained in the cathode. A study conducted at SRI International used different methods to purge the helium out of the metal, and the energy released was shown to be consistent with D + D -> ⁴He (however the number of samples were few, and the largest value of ⁴He measured was less than 50% of that in air)

[edit] Other nuclear effects

Neutron emissions near 2.45 MeV consistent with deuteron-deuteron fusion have been first reported by Jones in 1989. Since that time, there have been numerous reports of neutron and charged particle emission. The level of energy associated with these low level emissions is not observable calorimetrically.

The correlation between these emissions and excess heat has been under discussion. An anticorrelation between excess heat and neutrons was reported by Okamoto and coworkers. Neutron emission is associated with low current densities (around 30 mA / cm2) while excess heat appears over 250 mA / cm2, suggesting that the different effects have different operating regimes. A study shows that cathodes producing the largest excess heat at high current densities also shows the largest neutron emission at low current density.

Other researchers have detected very energetic charged particles. The appearance of such signals provides additional information that may be helpful in understanding the underlying physical process responsible for the new effects.

[edit] Conclusions

The experimental data shows evidence of:

• the existence of a physical effect that produces heat in metal deuterides.
• the production of ⁴He in amounts commensurate with a D + D -> ⁴He reaction mechanism
• a physical effect that results in the emission of energetic particles

The underlying process that produce these results are not manifestly evident from experiment. The scientific questions posed by these experiments are both worthy and capable of resolution by a dedicated program of scientific research.

[edit] Main conclusions of the review by the panelists

The 18 reviewers were split approximately evenly on the issue "Is there compelling evidence for power that cannot be attributed to ordinary chemical or solid states sources". However, those who accepted evidence of such power did not believe that a nuclear reaction could explain it: two-thirds of the reviewers did not feel that the evidence was conclusive for low energy nuclear reaction. One found the evidence convincing, and the remainder indicated that they were somewhat convinced.

Many reviewers noted that poor experiment design, documentation, background control and other similar issues hampered the understanding and interpretation of the results presented.

The nearly unanimous opinion of the reviewers was that funding agencies should entertain individual, well-designed proposal for experiments in this field. To resolve the controversy, they favored further investigation of the properties of deuterated metals and of the particles that they reportedly emit, using modern tools and techniques.

[edit] Reviewer comments

Here are some quotes from the reviewers:

• Review 1. "The evidence does not demonstrate that a new phenomenon is occurring."
• Review 2. "... there appears to be rather convincing evidence for the production of excess heat and for the production of 4He in metal deuterides. ... There is no convincing evidence for the occurrence of nuclear reactions in condensed matter associated with the reports of excess heat production."
• Review 3. "... the evidence strongly suggests a nuclear origin for the excess heat observed in palladium rods highly loaded with deuterium."
• Review 4. "This set of articles make a significant case for phenomena in the deuterium/palladium system that is (I) markedly different from that of the hydrogen/palladium system, (ii) supportive of the claim that excess energy is generated in the deuterium/palladium system, and (iii) without a coherent theoretical explanation."
• Review 5. "My feeling is that there should be no funds set aside for support of CF research but, if the DOE receives a proposal in this area which suggests some definitive research which settle some of the issues, it should consider it for support as it would any other proposal."
• Review 6. "I find nothing in the articles that I've read that convinces me that the new anomalies reported are not experimental artifacts."
• Review 7. "I find in summary that, even after all of the work that has been done, the case is spotty for the existence of the cold fusion phenomenon. I am not convinced by the evidence that I have seen ..."
• Review 8. "If the bottom line is that experiments in which x > 0.95 in PdDx (at room temperature) give anomalous effects reliably (even if achieving that high x is very difficult and very dependent on the materials science of the Pd), while heat balance is attained for x < 0.9 in PdDx (or when using PdHx at all x), we've got the start of science."
• Review 9. "Evidence for excess heat in LENR experiments is compelling and well established. ... The body of work that has resulted from LENR investigations is formidable and worthy of attention of the broader scientific community. It is unfortunate that a few vocal individuals have manage to stigmatize this field and those working in it."
• Review 10. "In a general summary of the calorimetric results, the observation of sudden and prolonged temperature excursions ..., has been made a sufficient number of times that, even if not totally reproducible, still have not been explained in terms of conventional chemistry or electrochemistry ... At this stage, I think the evidence suggests the possibility of such events, [but] cannot be considered conclusive beyond a reasonable doubt, for reasons alluded to above."
• Review 11. "the care in which the measurements are done for experiments that do show excess heat are convincing evidence of low energy nuclear reactions. ... There is strong evidence of nuclear reactions in palladium, and suggestions of reactions in the titanium foil experiments."
• Review 12. "There seem to be increasing evidence for the production of excess heat, even though the reason is totally unknown. ... Yes, it is likely that an unknown process (in materials physics or in nuclear physics) is responsible. However, the link to nuclear reaction is still not strong enough at the present time. ... The current evidence is not sufficiently conclusive to demonstrate that nuclear reactions occur in metal deuterides yet."
• Review 13. "... there is sufficient evidence to demonstrate that very low energy nuclear reactions can occur in condensed matter at rates that are totally unexpected"
• Review 14. "I am not persuaded that such energy has been produced."
• Review 15. "As one of the reviewers stated, one can never disprove something and this is my feeling about "cold fusion"."
• Review 16. "My opinion is that none of the experimental evidence directly presented to us is conclusive that nuclear reactions are occurring in these environments, but some of the evidence is certainly suggestive that they are."
• Review 17. "Most "nuclear" measurements (particle emission) are not convincing in comparison with the state of the art in low energy nuclear physics."
• Review 18. "Although experiments have become more sophisticated there is no new convincing or even tantalizing evidence for LENR."

[edit] Sources

• U.S. DoE 2004 Cold Fusion Review - U.S. Department of Energy review of 15 years of cold fusion experiments

[edit] Notes

[edit] Further reading

• A discussion of the impact of the DOE review by Scott R. Chubb