In reply to leaking pen's message of Sun, 7 Dec 2008 19:03:42 -0700: Hi, [snip] >fast neutrons can cause physical damage, de magnetize things, and >cause other issues, but i was under the impression that it would only >cause actual nuclear reactions with certain ALREADY radioactive >species. and i cant find anything online to the contrary. Care to >link some info on fast neutrons causing such reactions?
Google "spallation reactions". The neutron from a D-T reaction is 14 MeV, and the binding energy of most nucleons in any given nucleus is roughly 6 MeV, so the fast neutron certainly has enough energy to knock one free. Removal of a nucleon from a stable nucleus (or addition of one) often (but not always) results in the creation of a radio-isotope. Actually I was a bit surprised to find that generally such isotopes formed from the lighter elements have a rather short half life (seconds to minutes). A couple of important reactions with longer half lives are:- Fe56 - n -> Fe55 with a half life of 2.7 years and Cl35 + n -> Cl36 with a half life of 300000 years. Both of these are important in this regard because both elements are common in the environment, and both are readily incorporated into the human body. [snip] Regards, Robin van Spaandonk <[EMAIL PROTECTED]>
