In reply to Jones Beene's message of Fri, 13 May 2011 18:05:59 -0700: Hi, [snip] >-----Original Message----- >From: mix...@bigpond.com > >> One can see that the cross section for neutron absorption by Ni62 at >thermal energies (~ 2E-8 MeV) is about 14 barn. > > >Yes of course - that is a thermal neutron - which changes everything. There >is no thermalization mechanism in this reactor so these are out of the >question - and as stated, nickel is largely transparent to neutrons from >nuclear reactions unless thermalized. > > The "thermalization mechanism" is the next atom in the lattice. They all vibrate, and it's neigh on impossible to prevent an "ultra-cold" neutron from becoming thermalized in about a microsecond. Regards,
Robin van Spaandonk http://rvanspaa.freehostia.com/project.html