We present numerical results ]:or the specific heat of 3He-B in the weakcoupling-plus model. We find that the full temperature dependence of the specific heat is accurately determined by the specific heat jump at Tr This provides a test of the Tc/TF expansion scheme for calculating strong coupling effects in super[luid 3He.
In this paper we report calculations of temperature-dependent thermodynamic properties of superfluid 3He-B for 0 < T < To. The theoretical scheme underlying these calculations is the expansion of a stationary free-energy functional in powers of To~ TF which we have described in detail in Refs. 1 and 2. In this scheme the strong coupling corrections of leading order in Tc/TF are completely determined by Landau parameters and by weighted angular averages of the normal-state quasiparticle scattering amplitude. Keeping the weak coupling terms together with the leading strong coupling terms in the free energy functional defines what we will call the weak-coupling-plus model for superfluid 3He. We have previously used this model to calculate the coefficients in the Ginzburg-Landau free-energy functional, including magnetic field and gradient energies, and the B-phase magnetic susceptibility at T = 0.
Unfortunately, none of these results can be used to check the weakcoupling-plus model, because the strong coupling corrections to the various quantities are all given by different angular averages of the scattering amplitude. The most important point of the present paper is that the B-phase specific heat does test the weak-coupling-plus model (i.e., the To~ TF expansion). We find that although the specific heat CB(T) depends on three different averages of the scattering amplitude, the full temperature dependence of CB(T) [and also of the order parameter Ao(T)] is determined 589 i;1~22-2291.,'79.q/300 0589503.00/0 ..