The velocity of second sound near the la
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M.J. Adriaans; D.R. Swanson; J.A. Lipa
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Article
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1994
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Elsevier Science
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English
β 163 KB
We report new high precision data on the velocity of second sound close to the lambda transition of 4He at the saturated vapor pressure. The second sound wave is detected by a powdered salt pill of copper ammonium bromide in direct contact with the liquid helium. With a thermometer noise of < 10-1Β°K