Eric, The website you cite has data for ultracold neutrons (energy ~300 neV.) Could any LENR experiment ever produce such cold neutrons? Even at just room temp, thermal neutrons possess energy of ~30 meV. Wouldn't ultracold neutrons be a tiny part of the Boltzman distribution?
The thermal neutron cross section for Ni is quite high. Refer to: NGATLAS - Atlas of Neutron Capture Cross Sections http://www-nds.iaea.org/ngatlas2/ W-L electron capture may, or may not, occur, but AFAIK no one proposed that neutrons would be generated ultracold. Corrections are welcome. Cheers, Lou Pagnucco Eric Walker wrote: > On Thu, Mar 21, 2013 at 2:30 PM, Axil Axil <[email protected]> wrote: > > The specification of the ultra-low energy neutron was engineered to make > it >> virtually undetectable because it doesnât move far from the nucleus >> before >> its immense nuclear absorption cross section results in its almost >> immediate incorporation into the nucleus immediately after its creation. >> > > Nickel, to take one example, has a high neutron optical potential [1]. > When neutrons are very cold, they will reflect off of the nickel atoms to > a certain extent. A typical LENR experiment shows power on the order of > watts to tens of watts. If neutron capture were responsible for that kind > of power generation, there would be so many neutrons being generated that > a > significant portion would reflect off of the nickel substrate atoms, > thermalize and exit the system, to be picked up in GM counters. > > When neutrons have in fact been detected, the levels have usually been at > the threshold of the neutron detector. One presumes that if there were a > large number of thermalized neutrons exiting a system, they would would be > in quantities sufficient to go well beyond the threshold of detection. > > None of these are my own arguments. I am repeating what I have heard > elsewhere. Importantly, I am unfamiliar with the quantities that would be > needed to model this system and test these assumptions. But it seems > reasonable to ask an explanation predicated upon neutron capture to > address > these points. > > Eric > > [1] http://en.wikipedia.org/wiki/Ultracold_neutrons >
