Temperature Differences and Mutual Friction in He II Near Tλ

Abstract

An experiment has been performed to measure the temperatures at the ends of a cylindrical channel containing He II in the presence of a heat flux through the channel, near the lambda transition. Two channels of cross sections 1.1 mm2 and 2.2 mm2 were used and average temperatures ranged from within 1.0 × 10−2 K of Tλ. to within 3 × 10−5 K of Tλ. The results are fitted to a generalized Gorter–Mellink mutual friction expression of the form[Formula: see text]