Specific Heat of Liquid ${He}^{3}$ / ${He}^{4}$ Mixtures near the Junction of the $λ$ and Phase-Separation Curves. II

Measurements of the molar specific heat

c_{P, x}

of liquid

{He}^{3}

{He}^{4}

mixtures at saturated vapor pressure near the junction of the

λ

and phase-separation curves reported in an earlier paper have been used to calculate values of

{(\frac{\partial s}{\partial T})}_{P, x} = \frac{c_{P, x}}{T}

{(\frac{\partial φ}{\partial T})}_{P, x} = - {(\frac{\partial s}{\partial x})}_{P, T}

s

, and

φ - φ_{0}

at saturated vapor pressure throughout the junction region. Here

φ

is the difference

μ_{3} - μ_{4}

between molar chemical potentials,

x

is the mole fraction of

{He}^{3}

present, and the subscript 0 denotes the value of a quantity at the junction. Comparisons of

{(\frac{\partial s}{\partial T})}_{P, x}

and

{(\frac{\partial φ}{\partial T})}_{P, x}

with their respective upper bounds at the

λ

curve

{(\frac{ds}{dT})}_{P, λ} + {(\frac{d φ}{dT})}_{P, λ} {(\frac{dx}{dT})}_{P, λ}

and

{(\frac{d φ}{dT})}_{P, λ}

suggest but do not require that

{(\frac{\partial s}{\partial T})}_{P, φ} = \frac{c_{P, φ}}{T}

diverge all along the

λ

curve, as our results indicate that it does at the junction. Our results are consistent with the following asymptotic behaviors at the junction:

{(\frac{\partial s}{\partial T})}_{P, x, 0} - {(\frac{\partial s}{\partial T})}_{P, x} \sim {(T - T_{0})}^{1}

x = x_{0}

for

T > T_{0}

;

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Specific Heat of Liquid He3/He4 Mixtures near the Junction of the λ and Phase-Separation Curves. II