2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/22432Spin fluctuations of the archetypal heavy-fermion compound CeRu_2Si_2 have been investigated by neutron scattering in an entire irreducible Brillouin zone. The dynamical susceptibility is remarkably well described by the self-consistent renormalization (SCR) theory of the spin fluctuation in a phenomenological way, proving the effectiveness of the theory. The present analysis using the SCR phenomenology has allowed us to determine fourteen exchange constants, which show the long-range nature of the Ruderman-Kittel-Kasuya-Yosida interaction.5 pages, 3 figures, submitted to PRLStrongly Correlated Electronstext