ENERGY WEIGHTED SUMS FOR COLLECTIVE EXCITATIONS IN NUCLEAR FERMI-LIQUID

Model independent, m(1), adiabatic, m(-1), and high-energy, m3, energy weighted sums (EWS) for the isoscalar and isovector nuclear excitations are investigated within the framework of the kinetic theory adapted to the description of a twocomponent nuclear Fermi-liquid. For both the adiabatic and scaling approximations, the connection of the EWS m(-1) and m3 to the nuclear stiffness coefficients and the first-and zerosound velocities is established. We study the enhancement factor u I in the energy weighted sum m'(1) for the isovector excitations and provide the reasonable explanation of the experimental exceeding of the 100 % exhaustion of sum m'(1) for the isovector giant dipole resonances. We show the dependence of the enhancement factor kappa(I) on the nuclear mass number A and analyze its dependence on the Landau's isovector amplitude F'(1).