In reply to  Jones Beene's message of Wed, 8 Oct 2014 09:22:13 -0700:

Li7 + Ni58 => Ni59 + Li6 + 1.75 MeV
Li7 + Ni59 => Ni60 + Li6 + 4.14 MeV
Li7 + Ni60 => Ni61 + Li6 + 0.57 MeV
Li7 + Ni61 => Ni62 + Li6 + 3.34 MeV
Li7 + Ni62 => Ni63 + Li6 - 0.41 MeV (Endothermic!)

This series stops at Ni62, hence all isotopes of Ni less than 62 are depleted
and Ni62 is strongly enriched.

I have only briefly skimmed the report, but the basic reaction appears to be a
neutron transfer reaction where a neutron tunnels from Li7 to a Nickel isotope.
The excess energy of the reaction appears as kinetic energy of the two resultant
nuclei (i.e. Li6 & the new Ni isotope), rather than as gamma rays. Because there
are two daughter nuclei, momentum can be conserved while dumping the energy as
kinetic energy in a reaction that is much faster then gamma ray emission.
Because both nuclei are "heavy" and slow moving, very little to no
bremsstrahlung is produced. There is effectively no secondary gamma from Li6
because the first excited state is too high. (I haven't checked Li7). There is
unlikely to be anything significant from Ni because the high charge on the
nucleus combined with the "3" from Lithium tend to keep them apart (minimum
distance 31 fm).

It would be nice to know if the total amounts of each of Li & Ni in the sample
were conserved (I'll have to study the report more closely).

Robin van Spaandonk

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