Influence of direct inelastic scattering on (n, 2n) cross sections

Abstract The (n, 2n) cross sections were measured for the nuclei $ N^{14} $, $ F^{19} $, $ Ca^{48} $, $ Sc^{45} $, $ Mn^{55} $, $ Ni^{58} $, $ Cu^{65} $, $ Zn^{64} $, $ Zn^{66} $, $ Se^{82} $, $ Rb^{85} $, $ Rb^{87} $, $ Y^{89} $, $ Zr^{90} $, $ Mo^{92} $, $ Sn^{112} $, $ Sm^{144} $ at an excess ene...
Ausführliche Beschreibung

Abstract The (n, 2n) cross sections were measured for the nuclei $ N^{14} $, $ F^{19} $, $ Ca^{48} $, $ Sc^{45} $, $ Mn^{55} $, $ Ni^{58} $, $ Cu^{65} $, $ Zn^{64} $, $ Zn^{66} $, $ Se^{82} $, $ Rb^{85} $, $ Rb^{87} $, $ Y^{89} $, $ Zr^{90} $, $ Mo^{92} $, $ Sn^{112} $, $ Sm^{144} $ at an excess energy 3 MeV above threshold. In addition, the (n, 2n) cross sections for the nuclei $ Zn^{64} $, $ Zn^{70} $, $ Ga^{69} $, $ Ga^{71} $, $ As^{75} $, $ Mo^{100} $, $ Pb^{204} $ as well as the cross section of the process $ Pb^{204} $ (n, n’) $ Pb^{204m} $ were determined at 14,7 MeV bombarding neutron energy. At 3 MeV excess energy a strongN−Z dependence has been found in the (n, 2n) cross sections, valid for a broad region of neutron numbers which can be accounted for by the influence of direct inelastic scattering leading to low lying levels of the target nucleus. An empirical formula is given for calculating (n, 2n) cross sections. Ausführliche Beschreibung