These (n, 2n) cross sections are compared with the theoretical calculations performed by a new model including pre-equilibrium and statistical models. A good agreement between the experimental and calculated cross sections is obtained.

Activation cross sections for the (n, 2n) reaction on Nd, Sm, Gd and Yb have been measured at 14.6 MeV by using a Ge(Li) r-ray detector. The following cross sections (mb) have been obtained: 142 Nd 1,675±160, 148 Nd 1,789±147, 150 Nd 1,720±128, 154 Sm 2,010 ±137, 1soGd 2,173±152, 1 7 6Yb 2,226±152. These (n, 2n) cross sections are compared with the theoretical calculations performed by a new model including pre-equilibrium and statistical models. A good agreement between the experimental and calculated cross sections is obtained.