A systematic study of (n, 2n) cross sections at 14 MeV

The experimental (n,2n) cross sections around 14 MeV have been collected, analyzed, and evaluated. Data were taken from 124 nuclei for A=19–209 up to the end of 1983. Relation between σn, 2n and (N-Z)/A has been studied. No neutron shell effect is found. The cross sections for some nuclei have been calculated by using a statistical theory. The good agreement with the experimental σn, 2n at 14 MeV has been obtained in terms of a single set of fitting parameters.