Effective mass, spin fluctuations, and zero sound in liquid3He

x(T) and specific heat CV(T) are also calculated. These properties all depend upon the effective mass m*(k,v) of the Fermi quasiparticles making up the liquid. We use a model in which m* peaks near the Fermi surface to m*52.8, the Landau theory effective mass, and decreases toward the bare mass m*51 for quasi- particles away from the Fermi energy e F. The theory for all the properties may be viewed as Landau theory with an effective mass m*(e k)5m*(k) that decreases as the quasiparticle energy e k moves away from e F. The peaking of m* at e F is widely predicted in Fermi systems and the aim is to test how important this physical feature is in the dynamics of liquid 3He. We find thatSc(Q,v) and SI(Q,v) versus Q and T as well as x(T) are well reproduced by the model for the same m*(k). The CV(T) can be reproduced, but a much lower value of m*(k) at energies e k away from e F is required, m*.0.5, as found in previous calculations of CV(T). We conclude that the peaking of m* at e F is an important physical feature to include in calculations of S(Q,v) and that the quasiparticle model itself is inadequate for CV at higher temperatures.