Collective Modes in Atomic and Nuclear Systems

WeCollective modesin atomic systems considerCollective modesin Fermi systems twoFermi gas  applications of the Vlasov equation: the sound propagation in quantum homogeneous systems, and the giant resonancesGiant resonances in nuclear systems. At variance with classical fluids, which exhibit only the ordinary sound (henceforth called first sound), quantum systems also exhibit the so-called zero sound [LAN]. Its existence is supported directly by the experimental sound attenuation curves and indirectly by the models devised to interpret higher multipolarityMultipolarity giant resonances in nuclei.