Wikiversity/Cold fusion/Excess heat correlated with helium
Sources for this seminar are at Cold fusion/Excess heat correlated with helium/Sources
This study is at the core of understanding cold fusion. There are many papers reporting anomalous heat, with claims that the heat is beyond the possibility of chemistry. However, in the absence of confirmed and scaled-up demonstrations, the levels of heat are often small; while they may be convincing to those familiar with the calorimetry, they are not necessarily, by themselves, generally convincing, and some systematic error might be possible, and thus the conclusion that a nuclear reaction taking place is not solid, if based only on heat. As was commonly pointed out, a nuclear reaction will leave an ash, the nuclear product. If cold fusion is actually nuclear fusion, there will be elements left with higher atomic weight.
There was, early on, an intense search for the nuclear products expected from the known fusion of deuterium. Neutrons were sought, as was tritium; both of these would be copious products if the reaction were ordinary fusion. While tritium is so widely reported that it's difficult to discount all those reports, nevertheless, the amounts of tritium are roughly a million times lower than what would be seen if tritium were a major product. Neutrons are reported at levels a million times down from that.
There is only one nuclear product that is reported at levels commensurate with the observed anomalous heat, and that is helium. While there are, as well, reports of transmutations other than those to helium and tritium, they are also at quite low levels.
Helium is a rare branch in ordinary fusion. From the experimental evidence, however, helium may be the sole product of cold fusion (in palladium deuteride experiments). The helium branch of the ordinary d-d reaction is always accompanied by a gamma ray that carries off the high energy of fusion. Such gamma rays, which would be highly penetrating and, indeed, dangerous, are not observed. X-rays are observed, there are wide reports, but, again, they are at low levels.
It appears that cold fusion is a miracle, a mystery. If the experimental evidence is not misleading, cold fusion produces helium from deuterium, without radiation or radioactive byproducts, unless those are at very low levels or energies. All the energy released from fusion, it appears, ends up as heat. That this was unexpected would be an understatement. It is not impossible, however, the well-known "impossibility proofs" for cold fusion depended on assumptions about the reaction, they would not apply to what Pons and Fleischmann actually claimed, an "unknown nuclear reaction.
The implications for energy generation, if it becomes possible to control this reaction, to reliably produce it, turning the effect on and off at will, are enormous. However, we will not examine those implications in this seminar, and they would distract us.
Rather, we will look at what is fundamental: what is the evidence for a correlation between heat and helium in cold fusion experiments (with palladium deuteride)? What is the observed ratio? Are there possible artifacts that could explain the observations without requiring a nuclear reaction?
Heat/helium work uses two radically different measurements in a single experiment. The first is the measurement of heat, which uses standard techniques of calorimetry. The second is the measurement of helium, typically done with samples subjected to mass spectrometry. While there are published papers where we only have data from a single experiment, some reports are of extensive series of experiments, under conditions where only some cells showed anomalous heat. The helium data matches those results: no heat, no helium. And with few exceptions (we will look at them), if there is heat, there is helium, and at a ratio consistent with deuterium fusion to helium.
As we will see, there have been some attempts to propose a non-nuclear explanation for this, and we will look at those, but, from the outset, the level of coincidence involved, that, accidentally, a heat artifact and a helium artifact would match each other, across many experiments, at close to the fusion ratio, would be enormous. Is this plausible?
And how would we test this?
This resource is being developed, now, as a study of heat and helium, and it will be used in a process which will propose further work with the heat/helium ratio, with the goal of measuring it more precisely, as well as addressing any possible artifacts. Skeptical participation is not only invited, it is highly desirable.
Naturally, it is possible that there could be error in measuring heat. As well, there can be error in measuring helium, plus helium is present in the atmosphere, naturally, at levels that are often above those reported in heat/helium experiments. However, there is enough data on the heat/helium ratio to require that, for the correlation to be as consistent as it has been found to be, there must be some connection between the two measurements. An example of what has been proposed is that heat or something connected with the heat causes leakage of helium from the atmosphere. Is this plausible? The subpage will examine what has been proposed.
User:Abd has written a review of the heat/helium experiment, which has been peer-reviewed and has been published in w:Current Science, February 25, 2015. The subpage will collect commentary on this review, note corrections, and allow discussion.