Nuclear Data Sheets for A = 251

Abstract

Nuclear spectroscopic information for known nuclides of mass number 251 with Z = 96 to 102 (Cm,Bk,Cf,Es, Fm,Md,No) and N = 155 to 149 have been evaluated and presented together with adopted energies and Jπ of levels in these nuclei. No excited state data are yet available for 251Cm. This evaluation supersedes previous full evaluation of A = 251 by A. Artna-Cohen (1999Ar21) with literature cutoff date of Jul 1999. Inconsistencies and discrepancies are noted. The adopted values of level energies, level spins and parities are given, and γ-ray energies, γ-ray intensities, as well as other nuclear properties are presented. The references, Jπ arguments, and necessary comments are given. Theoretical studies are given as comments. New measurements have been reported in 251No, 251Md, 251Cf and 251Es. All adopted Q values are from 2003Au03. 2004Pa31 give calculated neutron separation energy by a macroscopic-microscopic approach.