Slow-Neutron Scattering Cross Sections of Terbium, Ytterbium, and Lutetium

The coherent neutron scattering cross sections of terbium, ytterbium, and lutetium as determined from the neutron diffraction measurements on TbC₂, YbC₂, Yb, and Lu metals are found to be 7.2±{}0.4, 20.0±{}0.4, and 6.70±{}0.37 barns, respectively, all with amplitude of positive phase. The total scattering cross sections of Tb, Yb, and Lu and the magnetic scattering cross sections of Tb⁺³ and Yb⁺³ are evaluated for thermal neutron energies. The neutron diffraction data also show the Debye temperatures of Yb and Lu metals to be 109±{}5^∘{}K and 161±{}7^∘{}K, respectively.