Theory and Satellite Experiment for Critical Exponent alpha of lambda-Transition in Superfluid Helium

TL;DR

This paper combines theoretical seven-loop perturbation calculations with satellite experimental data to precisely determine the critical exponent alpha of the lambda-transition in superfluid helium, confirming the theoretical predictions.

Contribution

It provides a refined theoretical estimate of alpha using advanced perturbation theory and validates it with satellite experimental measurements.

Findings

Theoretical alpha estimate: -0.01126 ± 0.0010

Experimental alpha value: -0.01056 ± 0.00038

Excellent agreement between theory and experiment

Abstract

On the basis recent seven-loop perturbation expansion for nu^{-1} = 3/(2 - alpha) we perform a careful reinvestigation of the critical exponent alpha governing the power behavior |T_c-T|^{- alpha} of the specific heat of superfluid helium near the phase transition. With the help of variational strong-coupling theory. we find alpha = - 0.01126 +- 0.0010, in very good agreement with the space shuttle experimental value alpha = - 0.01056 +- 0.00038.