The attenuation of sound in solutions of 3He and 4He

✍ Scribed by E.W. Guptill; A.M.R. Van Iersel; R. David

• Publisher: Elsevier Science
• Year: 1958
• Weight: 241 KB
• Volume: 24
• Category: Article
• ISSN: 0031-8914
• DOI: 10.1016/s0031-8914(58)80119-6

✦ Synopsis

Synopsis

Measurements have been made of the attenuation of first sound in mixtures of 4He and 8He for differeht 8He concentrations (11, 3, 1 and 0.5%) and at temperatures between 0.88°K and the 2-point. In the neighbourhood of 1.0°K the attenuation is diminished greatly by the addition of 8He. Within our accuracy the attenuation is proportional to the frequency squared between 7.3 and 12.1 MHz.

However, the variation of the inner diameter of the cylinder must be an order of magnitude less than 1/Q which is approximately 10 -5 in 4He, at 6 MHz. This requires that the cylinder be off-~ound by not more than 0.1/~.