On Thu, Jul 11, 2013 at 12:11 PM, H Veeder <hveeder...@gmail.com> wrote:
How many well known collisions produce outgoing particles who kinetic > energy is approx. 100 times that of the incoming particles? > > Can it be compared with known collisions? > It was closer to 15,000 times the original energy (5,000,000 eV / 350 eV), after having traversed ~1 um of titanium (or, possibly, some daughter particle resulting from a chain reaction of some kind that occurred closer to the exiting side of the foil). The presence of the foil complicates things, because it's not clear how far the daughter had to travel through it. The longer it had to travel, the more it would slow down, I think, especially if it was not initially aligned along an open pathway in the crystal structure. The authors speculated that the mystery particle was tritium on the basis of the energy difference in the energy peak when the 200 V detecter bias was turned off (silicon surface-barrier detector spectra respond to changes in voltage, apparently). The authors did not offer a possible reaction. Another possibility apart from a nuclear reaction was that background radiation was mistakenly associated with the incoming beam collisions. They only saw events in four of nine experiments, and the particles could have been cosmic rays or something similar. Also interesting is the fact that there was an earlier experiment by a group in Germany with a very similar setup that I just read about, and they saw nothing that could not be explained by normal dd reaction cross sections. But I don't think they saw anything above noise in the 300 eV range, and their foils were 3 um thick. Eric
