title: Measurement of the normal-fluid velocity in superfluids.
abstract: Numerical calculations of (finite temperature) superfluid vortex ring propagation against a particulate sheet show that the solid particle trajectories collapse to a very good approximation to the normal-fluid path lines. We propose an experiment in which, by measuring the solid particles' velocities, direct information about the instantaneous normal-fluid velocity values could be obtained.
authors.affiliation: School of Mathematics, University of Newcastle, Newcastle upon Tyne, NE1 7RU, United Kingdom.
authors.forename: Demosthenes
authors.initials: D
authors.lastname: Kivotides
authors.forename: Carlo F
authors.initials: CF
authors.lastname: Barenghi
authors.forename: Yuri A
authors.initials: YA
authors.lastname: Sergeev