In reply to Stephen Cooke's message of Fri, 20 May 2016 12:04:22 +0200: Hi, [snip] >Is there a relationship between the cross-section for slow neutron capture in >particular nuclei and the nucleus excitation energy needed in the nucleus to >cause neutron spallation? > >For example B10 has a high neutron cross-section. Is there s relationship >between this and the energy needed for Neutron spallation from B11?
That's what I would expect too. Nuclei with a high neutron capture cross-section really "want" to have that extra neutron, because they become much more stable. Conversely, removing the neutron from the new stable nucleus should be very difficult. Compare the neutron capture energy release with that of other nuclei. I would expect it to be larger. In this case, 10B+n => 11B + 11.454 MeV (That's a lot for a single particle capture reaction). Another high capture cross-section reaction is:- 3He+n => 4He + 20.578 MeV which is why He3 is used in some neutron detectors. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
