title: Helium mass flow through a solid-superfluid-solid junction.
abstract: We report the results of flow experiments in which two chambers containing solid ^{4}He are connected by a superfluid Vycor channel. At low temperatures and pressures, mechanically squeezing the solid in one chamber produced a pressure increase in the second chamber, a measure of mass transport through our solid-superfluid-solid junction. This pressure response is very similar to the flow seen in recent experiments at the University of Massachusetts: it began around 600 mK, increased as the temperature was reduced, then decreased dramatically at a temperature, T_{d}, which depended on the ^{3}He impurity concentration. Our experiments indicate that the flow is limited by mass transfer across the solid-liquid interface near the Vycor ends, where the ^{3}He collects at low temperature, rather than by flow paths within the solid ^{4}He.
authors.affiliation: Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2E1.
authors.forename: Zhi Gang
authors.initials: ZG
authors.lastname: Cheng
authors.affiliation: Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2E1.
authors.forename: John
authors.initials: J
authors.lastname: Beamish
authors.affiliation: Laboratoire de Physique Statistique de l'ENS, associé au CNRS et aux Universités Denis Diderot et Pierre et Marie Curie, 24 Rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Fefferman
authors.affiliation: Laboratoire de Physique Statistique de l'ENS, associé au CNRS et aux Universités Denis Diderot et Pierre et Marie Curie, 24 Rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Souris
authors.affiliation: Laboratoire de Physique Statistique de l'ENS, associé au CNRS et aux Universités Denis Diderot et Pierre et Marie Curie, 24 Rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Balibar
authors.affiliation: DEN/DPC/SECR/LRMO, CEA Saclay, F-91191 Gif sur Yvette Cedex, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Dauvois