On Mar 23, 2010, at 7:45 AM, Jones Beene wrote:
[snip a bunch of stuff with which I agree]
I wrote: "Windom and Larsen estimate slow neutrons to be absorbed in
less than a nanometer, 10^-9 meter, about 10 angstroms. That is about
10 hydrogen atoms, or 3 Pd atoms in width. If neutrons can make it
0.5 Å into a nearby hydrogen nucleus they can make it 1.79 Å into Pd
or another lattice element just as well. There are no other nuclei in
the way, so cross sections are not even an issue. Heavier atoms are
not all that much bigger than light ones because atomic radius does
not grow much with atomic number, e.g. radii in angstroms: Pd 1.79,
Au 1.79, Ni 1.62, Li 2.05, K 2.77, Al 1.82, Cu 1.57, Pb 1.81. If
fusion is occurring at a rate sufficient to account for excess heat
then NA should occur at a huge rate also, one that could not possibly
be missed."
There is a hopefully fairly obvious typo I made in the above. The
"0.5 Å" should be "3.5 Å", a rough approximation. The lattice
constant for room temperature Pd is 3.89 Å and for Ni is 3.52 Å. I
should also note that "NA" stands for neutron activation.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
