On Mon, Jan 13, 2014 at 10:16 AM, Foks0904 . <[email protected]> wrote:
And while W-L is likely smoke and mirrors, lack of neutron detection does > not refute the theory, because as W-L states their "Ultracold" Neutrons are > captured so quickly as to evade detection. Convenient, no? > Even the fact that the neutrons are hypothesized to be very slow does not seem to be all that convenient upon further reflection. The amount of neutrons needed to generate the kind of heat seen in CF experiments would be very high indeed -- let's say on the order of 10E12 per second, just to put a number on it. The neutron capture cross section would need to be extremely large in order for the nickel lattice sites to absorb all of those neutrons. But the capture cross section is finite and is not arbitrarily large, and indeed nickel has a high "neutron optical potential," meaning that slow neutrons have an increased likelihood of bouncing off of nickel atoms [1]. Some of those neutrons are going to have to exit the system. If you have a ginormous number of neutrons being created per second, and even one percent are not captured, that is a lot of neutrons: 10E12 * 0.01 = 10E10 per second. I suspect, however, that 0.99 percent neutron capture is a wild and wonderful fantasy, and that the actual maximum capture cross section, even for nearly stationary neutrons, is far lower. Those neutrons are going to tumble all over the place, thermalize with the environment, set off gamma rays as they interact with water and surely result in a lot of clicks on any nearby geiger counters. But assume for the moment that 99.99999999 percent of the neutrons are captured in a special W-L LENR reaction. The reaction would need to be very special, because normally neutrons activate a host material, but these ones can't, because activation is not something that is generally seen in CF experiments. I suspect the reason W-L got so much traction is because it does away with the Coulomb barrier problem (by fiat). That is a very attractive thing to hobbyists like me, who know enough about nuclear physics to know that Coulomb repulsion is a major difficulty to be dealt with (I used to like W-L, btw). Eric [1] http://en.wikipedia.org/wiki/Ultracold_neutrons#Reflecting_materials
