Interpretation of experimental data near λ-transition point in liquid helium
Institute of Mathematics and Computer Science, University of Latvia,
29 Rainja Boulevard, LV-1459 Riga, Latvia
Corresponding author: a email@example.com
Revised: 18 April 2005
Published online: 13 July 2005
The recently published experimental data for specific heat Cp of liquid helium in zero gravity conditions very close to the λ–transition have been discussed. We have shown that these data allow different interpretations. They can be well interpreted within the perturbative RG approach and within our recently developed theory, as well. Allowing the logarithmic correction, the corresponding fits lie almost on top of each other over the whole range of the reduced temperatures t (for bin averaged data) . However, the plot of the effective exponent suggests that the behaviour of Cp, probably, changes very close to . To clarify this question, we need more accurate data for . In addition, we show that the experimental data for superfluid fraction of liquid helium close to within can be better fit by our exponents , than by the RG exponents and . The latter ones are preferable to fit the whole measured range where, however, remarkable systematic deviations appear. Our estimated value of the asymptotic exponent ν well agrees with the theoretical prediction .
PACS: 05.70.Jk – Critical point phenomena / 67.40.Kh – Thermodynamic properties / 65.20.+w – Thermal properties of liquids: heat capacity, thermal expansion, etc.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005