NMR-STUDY OF MAGNETIC EXCITATIONS IN CENISN

The anisotropies of the Knight shift and the nuclear spin-lattice rela xation time (T-1) at the Sn sites have been measured up to 300 K with a magnetically aligned powder sample of CeNiSn. In contrast to the res ults of previous neutron scattering measurements, the anisotropy of 1/ T-1 is weak and almost temperature (T)-independent. This indicates tha t the substantial spectral weight exists in the higher energy region t han the quasielastic magnetic excitation at high T. Above about 60 K, 1/T-1 increases linearly with T, suggesting that the T dependence of t he quasielastic line width is weak.