At 12:03 PM 9/3/2012, Jeff Berkowitz wrote:
I don't know how Kim at Purdue is regarded in this group, but aside from his theoretical work, his ICCF-17 paper proposes three experiments along these lines. They are: (a) Determine the velocity distribution of deuterons in metals, which he states "is expected to be different" from an ideal gas. (b) Additional measurements of the diffusion rates in metals. (c) Put metal nanoparticles in 4He and see what happens.
I replied with an examination of Kim's paper. Now I'm looking at the above comment. Jeff gives three proposed experiments. He's not accurately stated what Kim has prooposed, not with all of these.
a. Yes. And it is expected to be different from the distribution in an ideal gas, that's fairly obvious. How different is not known.
b. Kim writes, "Experiments are proposed to measure the diffusion rates of both deuterons and protons in a metal as a function of temperature. When the BEC of deuterons in a metal occurs, it is expected that the deuteron diffusion rate will increase substantially more than that of proton. We need to explore a number of other experimental methods for observing the superfluidity, such as the use of torsional oscillators." Kim is proposing more than a measurement of the diffusion rates, which are known, at least for relatively high temperatures; he's looking for variation with temperature, presumably at very low temperatures. The diffusion rate is related to the velocity distribution, by the way.
c. He does not propose putting metal nanoparticles in 4He. Rather, he is proposing cooling nanoparticle PdD to liquid 4He *temperatures*.
Kim's second experiment is quite unlikely to show much, but it's possible, and we should always remember that Pons and Fleischmann expected to find nothing in PdD, even very highly loaded. In fact, with hindsight, they *did* find nothing in highly loaded PdD itself, probably. But they accidentally created nuclear-active environment, probably on the surface. I say it is unlikely to show much because the reaction rate is quite slow, so almost all the deuterium is not in BEC form. But maybe something would show up!
As to the third, I'd be surprised if it hasn't been tried, it's simple enough. Against this possibility is that the FPHE (PdD) is a reaction that increases in rate with temperature. Watch out! Don't just dump a pile of highly loaded PdD into liquid helium!
(There is some reason to think that highly loaded PdD might also be susceptible to pressure ignition, using an explosive trigger. LANL apparently tried it without success, but maybe they got some parameter wrong. My "don't try this at home" variation would be making some very highly loaded PdD and then whacking it with a sledge hammer. Almost certainly, nothing would happen. But, just think: don't try an experiment if you are not prepared for it to work a lot better than you imagine! Pons and Fleischmann, in about 1984, lost a lab bench and some inches of concrete from the floor. But they might just as easily have lost the whole building, we don't know. They scaled down, then, for very good reasons, and then skeptics complained about the size of the effect....)
