Gregory F. Spencer

Experimental determination of the\(\hat n\)-texture of superfluid3He-B in a cylinder

AbstractThe

Sweeping a persisting superconducting magnet with a transformer

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Considerations on burst disk use in closed-cycle helium liquefier systems

texture formed in a 2mm diameter cylinder of superfluid3He-B has been studied by continuous wave NMR near Tc. The experiments were performed at low pressures (0.82 and 2.89 bar) and using an axial magnetic field of 286 G to preserve the cylindrical symmetry of the texture. A method of deconvolution of the NMR lineshapes is presented along with the texture map obtained from the data. The texture resembled the calculated flare-out texture although differing in details including the existence of an azimuthal component to

NMR studies of B-phase superfluid 3He at low pressures

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Extreme nonlinear damping by the quasiparticle gas in superfluid ³He-/ital B/ in the low-temperatur

(r). By comparison to the Ginzburg-Landau expressions expected to hold near TC, the magnetic bending length of RCHB=37(1−T/Tc)1/2 cm G was found, verifying the Ginzburg-Landau prediction.

Experimental determination of the <img src="/fulltext-image.asp?format=htmlnonpaginated&src=L44684GP

A novel design for a low‐temperature valve is presented. Designed to be used on fill‐line capillaries and flow lines in low‐temperature apparatus, the valve has nearly zero dead volume as well as a very small total volume. It employs no metallic bellows as in standard valve designs. Instead, a Kapton membrane is epoxied into a cylindrical form to provide a flexible diaphragm, which is activated by pressurized helium. The valve is simple to construct, having only one machining operation, and uses materials readily available. It has been tested in liquid helium to be leaktight above Tλ with a 1‐bar pressure differential across the capillary containing the valve.