Spin Distribution in Nuclear Level Schemes

The spin cut-off parameter sigma has been determined for experimental low-excitation energy spin distributions of 310 nuclei between F-18 and Cf-251 (more than 8000 levels with their spin). The results indicate a weak dependence on the mass number, sigma(2) similar to A(0.30), and a strong even-odd spin staggering in the even-even nuclei.