A Study of the Trapping of Superfluid Persistent Currents in Superleaks.
Abstract
Persistent currents in superleaks in contact with bulk superfluid helium were investigated using doppler shifts of the two acoustic modes of an annular resonator partially packed with superleak, and with a simple gyroscopic technique. The two modes have been studied between the temperatures 1.2K and the lambda temperature for annuli filled to various depths with superleak. The doppler shifts of the acoustic modes were used to obtain the persistent current velocities in the unpacked and packed regions of the resonator. Observations were made on a bare superleak using a simple gyroscopic apparatus suspended from a torsion wire. When the superleak is tilted with a persistent current, the change in the angular momentum vector leads to a torque which causes the gyroscope to swing on the torsion wire. The temperature dependence of the current in the bare superleak was found to be approximately the same as that observed in other experiments on a superleak completely enclosed by metal walls.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1975
- Accession Number
- ADA020927
Entities
People
- Joseph Edward Heiserman
Organizations
- University of California, Los Angeles