December 1, 2004
The Department of Energy’s (DOE) Office of Science (SC) was approached in
late 2003 by a group of scientists who requested that the Department revisit
the question of scientific evidence for low energy nuclear reactions. In 1987
Pons and Fleischmann first reported the production of “excess” heat in a Pd electrochemical
cell, and postulated that this was due to D-D fusion (D=deuterium), sometimes
referred to as “cold fusion.” The work was reviewed in 1989 by the Energy
Research Advisory Board (ERAB) of the DOE. ERAB did not recommend the
establishment of special programs within DOE devoted to the science of low
energy fusion, but supported funding of peer-reviewed experiments for further investigations.
Since 1989, research programs in cold fusion have been supported by various universities,
private industry, and government agencies in several countries.
In response to the above request, the Office of Science agreed to a peer
review of the experimental data and supporting theory since the 1989 ERAB
review. The scientists who made this request were asked to generate a review
document that identified the most significant experimental observations and publications,
and those areas where additional work would appear to be warranted. This
document, entitled “New Physical Effects in Metal Deuterides,” was prepared 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 (hereafter
referred to as the proposers). Together with supplemental material, said
document was submitted to DOE in July 2004 (Attachment 1).
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. 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. Individual
comments from reviewers were requested following the presentations.
In total, 18 individual reviewer comments were received by DOE.
Reviewers were asked to respond to the following charge in their
evaluation of the written and/or oral material: (1) To examine and evaluate the
experimental and theoretical evidence for the occurrences of nuclear reactions
in condensed matter at low energies (less than a few electron volts). (2) To
determine whether the evidence is sufficiently conclusive to demonstrate that
such nuclear reactions occur. (3) To December 1, 2004 determine whether there is a scientific case for continued
efforts in these studies and, if so, to identify the most promising areas to be
pursued. Copies of the charge letter and accompanying instructions regarding
conflict of interest and confidentiality are attached (Attachment 2).
The review document submitted (Attachment 1) focused on “a subset of
research from two areas” in the field of low energy nuclear reactions: (1)
“selected issues associated with excess heat production in deuterated metals”
and (2) “some aspects of nuclear emissions from deuterated metals.” According
to the review document, D-D fusion has been demonstrated to occur spontaneously
when D is introduced into Pd metal at very high concentrations (D/Pd ~ 0.95).
According to the review document, these demonstrations include purported
production of anomalous energy, helium, tritium, and a variety of elements not
initially present in the experimental container.
The material presented in the review document and oral presentations
focused on electrochemical reactions in the Pd/D2O system, evidence for
excess heat and nuclear reaction products, and the current theoretical
framework that has been used to describe the observations. Data were also
presented on the use of ion beams and glow discharge systems used to study the
Pd,Ti/D and Pd,Ti/H systems. The review only addressed “light element”
experiments, namely H or D fusion.
The proposers state that the results from the research provide evidence
for effects in three categories, as summarized in the review document’s
Conclusions Chapter:
1. “The existence of a physical effect that produces heat in metal
deuterides. The heat is measured in quantities greatly exceeding all known
chemical processes and the results are many times in excess of determined
errors using several kinds of apparatus. In addition, the observations have
been reproduced, can be reproduced at will when the proper conditions are
reproduced, and show the same patterns of behavior. Further, many of the
reasons for failure to reproduce the heat effect have been discovered.”
2. “The production of 4He as an ash associated with this
excess heat, in amounts commensurate with a reaction mechanism consistent with
D+D 4He
+ 23.8 MeV (heat)”.
3. “A physical effect that results in the emission of: (a) energetic
particles consistent with d(d,n)3He and d(d,p)t fusions reactions,
and (b) energetic alphas and protons with energies in excess of 10 MeV, and
other emissions not consistent with deuteron-deuteron reactions.”
The material presented can be found at http://www.sc.doe.gov. Following
the oral presentations, reviewers requested additional documentation from the
presenters. This supplemental material can also be found at the indicated link.
Detailed Summary of Reviewer Response to Charge
Elements Since
the 1987 report by Pons and Fleischmann, scientists have continued to
investigate the conditions responsible for the anomalous heat production in an
attempt to establish reproducible conditions for the generation of excess
energy, quantify the amount of energy being released, and confirm the
hypothesis that the energy is a consequence of nuclear fusion by detecting the
expected nuclear reaction products.
Below is a summary of the reviewer responses to the three charge elements,
written by DOE program managers and intended to give an overall sense of the
reviewers’ comments. The entire charge letter is December 1, 2004 enclosed as Attachment 2. The
redacted reviewer comments (only their names and institutions were removed)
have been sent to the proposers.
Charge Element 1: Examine and evaluate the
experimental evidence for the occurrences of nuclear reactions in condensed
matter at low energies (less that a few electron volts).
The experimental evidence presented by the review document and oral
presentations for the occurrences of nuclear reactions consisted of two general
types: excess power production from an electrolytic cell containing metal
electrodes (palladium is the typical metal) with a deuterated electrolyte; and measurement
of expected fusion products such as 4He in electrolytic cells, or any
of the other expected products observed in hot fusion, proton + triton (the
nucleus of tritium, consisting of two neutrons and one proton) or neutron + 3He,
in a variety of experiments.
The excess power observed in some experiments is reported to be beyond
that attributable to ordinary chemical or solid state sources; this excess
power is attributed by proponents to nuclear fusion reactions.
Evaluations by the reviewers ranged from: 1) evidence for excess power is
compelling, to 2) there is no convincing evidence that excess power is produced
when integrated over the life of an experiment. The reviewers were split
approximately evenly on this topic. Those reviewers who accepted the production
of excess power typically suggest that the effect seen often, and under some
understood conditions, is compelling. The reviewers who did not find the
production of excess power convincing cite a number of issues including: excess
power in the short term is not the same as net energy production over the entire
of time of an experiment; all possible chemical and solid state causes of
excess heat have not been investigated and eliminated as an explanation; and
production of power over a period of time is a few percent of the external
power applied and hence calibration and systematic effects could account for
the purported net effect. Most reviewers, including those who accepted the
evidence and those who did not, stated that the effects are not repeatable, the
magnitude of the effect has not increased in over a decade of work, and that
many of the reported experiments were not well documented.
The hypothesis that excess energy production in electrolytic cells is due
to low energy nuclear reactions was tested in some experiments by looking for D
+ D fusion reaction products, in particular 4He, normally produced
in about 1 in 107 in hot D + D fusion
reactions. Results reported in the review document purported to show that 4He
was detected in five out of sixteen cases where electrolytic cells were
reported to be producing excess heat. The detected 4He was typically very
close to, but reportedly above background levels. This evidence was taken as
convincing or somewhat convincing by some reviewers; for others the lack of
consistency was an indication that the overall hypothesis was not justified.
Contamination of apparatus or samples by air containing 4He
was cited as one possible cause for false positive results in some
measurements.
Beam experiments not involving electrolytic cells were reported in the review document and oral presentation, purport to provide evidence for low energy nuclear reactions. These experiments involved low energy deuterium beams impinging on deuterium loaded metal foils such as titanium. The studies were designed to investigate screening effects in materials that would be relevant to fields such as nuclear astrophysics. Those reviewers who commented on these studies generally viewed them favorably, but to many reviewers these studies were somewhat peripheral to the main thrust of this review.
A similar line of investigation involved counting deuterium loaded foils
to observe the products for the standard fusion reaction channels, proton +
triton or neutron + 3He, with particle detectors and coincidence techniques.
Indications of purported detection of proton-triton coincidences at a low level
were presented. Even skeptical reviewers cited this work as one line of
investigation that could be pursued to a clear conclusion. However, the results
were not convincing to some reviewers in regard to the occurrence of low energy
nuclear reactions. Experts noted many deficiencies in the techniques, methods,
and interpretation of the data presented. The present state-of-the-art for
tracking coincidences and the methodology for low data rate experiments is far
advanced beyond methods used in the experiment contained in the review document
and oral presentations.
Two-thirds of the reviewers commenting on Charge Element 1 did not feel
the evidence was conclusive for low energy nuclear reactions, one found the
evidence convincing, and the remainder indicated 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.
Charge Element 2: Determine whether the evidence
is sufficiently conclusive to demonstrate that such nuclear reactions occur.
Reviewers expert in nuclear physics noted that the cold fusion mechanism
put forward by proponents is not in accord with presently accepted knowledge of
D + D fusion. Specifically, D + D fusion is accompanied by the production of
protons, neutrons, tritons, 3He, 4He and high energy
gamma rays, all in well known proportions. The fusion channel resulting in 4He
and high energy gamma rays occurs approximately only once for every 107 D
+ D fusion reactions. These characteristic proportions for the production of
the fusion products are found for every energy of the incident deuteron
measured so far, down to the lowest that has been measured.
The review document and oral presentations made the argument that the
branching ratios are different at low energies and that in cold fusion, 4He
fusion channel is predominant. According to the review document, no high energy
gamma rays appear to accompany the 4He, as is observed in D-D fusion reactions.
Instead, the approximately 24 MeV in energy resulting from D-D fusion was
purported to appear as heat in the material lattice. To explain these unusual
characteristics, the reviewers were presented with a theoretical framework that
purported to describe how collective energy from the material lattice couples
to a deuteron pair to induce fusion, how the only fusion reaction channel that occurs
would be the production of 4He, and how all the energy is
coupled back into the material in the form of heat instead of high energy
gamma-rays. The reviewers raised serious concerns regarding the assumptions
postulated in the proposed theoretical model for the explanation for 4He
production.
The preponderance of the reviewers’ evaluations indicated that Charge
Element 2, the occurrence of low energy nuclear reactions, is not conclusively
demonstrated by the evidence presented. One reviewer believed that the
occurrence was demonstrated, and several reviewers did not address the
question.
Charge Element 3: Determine whether there is a
scientific case for continued efforts in these studies and, if so, to identify
the most promising areas to be pursued.
The nearly unanimous opinion of the reviewers was that funding agencies
should entertain individual, well-designed proposals for experiments that
address specific scientific issues relevant to the question of whether or not
there is anomalous energy production in Pd/D systems, or whether or not D-D
fusion reactions occur at energies on the order of a few eV. These proposals
should meet accepted scientific standards, and undergo the rigors of peer
review. No reviewer recommended a focused federally funded program for low
energy nuclear reactions.
Reviewers identified two areas where additional research could address
specific issues. One is the investigation of the properties of deuterated
metals including possible effects of alloying and dislocations. These studies
should take advantage of the modern tools for material characterization. A second
area of investigation is the use of state-of-the-art apparatus and techniques
to search for fusion events in thin deuterated foils. Several reviewers
specifically stated that more experiments similar in nature to those that have
been carried out for the past fifteen years are unlikely to advance knowledge
in this area.
While significant progress has been made in the sophistication of
calorimeters since the review of this subject in 1989, the conclusions reached
by the reviewers today are similar to those found in the 1989 review.
The current reviewers identified a number of basic science research areas
that could be helpful in resolving some of the controversies in the field, two
of which were: 1) material science aspects of deuterated metals using modern
characterization techniques, and 2) the study of particles reportedly emitted
from deuterated foils using state-of-the-art apparatus and methods. The
reviewers believed that this field would benefit from the peer-review processes
associated with proposal submission to agencies and paper submission to
archival journals.
Attachment 1: Review document submitted by requesters,
"New Physical Effects in Metal Deuterides."
Attachment 2: Charge letter to reviewers