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Thermal Conductivity Measurements of Helium 4 Near the Lambda-Transition Using a Magnetostrictive Low Gravity Simulator

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dc.contributor.author Larson, Melora en_US
dc.contributor.author Israelsson, Ulf E. en_US
dc.date.accessioned 2004-10-05T06:33:14Z
dc.date.available 2004-10-05T06:33:14Z
dc.date.issued 1995-03 en_US
dc.identifier.citation San Jose, CA en_US
dc.identifier.clearanceno 94-1563 en_US
dc.identifier.uri http://hdl.handle.net/2014/33587
dc.description.abstract There has been a recent increase in interest both experimentally and theoretically in the study of liquid helium very near the lambda-transition in the presence of a heat current. In traditional ground based experiments there are gravitationally induced pressure variations in any macroscopic helium sample that limit how closely the transition can be approached. We have taken advantage of the finite magnetic susceptibility of He 4 to build a magnetostrictive low gravity simulator. The simulator consists of a superconducting magnet with field profile shaped to counteract the force of gravity in a helium sample. When the magnet is operated with B x *B/*z = 21T²/cm at the location of the cell, the gravitationally induced pressure variations will be canceled to within 1% over a volume of 0.5 cm in height and 0.5 cm in diameter. This technique for canceling the pressure variations in a long sample cell allows the lambda-transition to be studied much closer in reduced temperature and under a wider range of applied heat currents than is possible using other ground based techniques. Preliminary results using this low gravity simulator and the limitations of the magnetostrictive technique in comparison to doing space based experiments will be presented. en_US
dc.format.extent 45161 bytes
dc.format.mimetype application/pdf
dc.language.iso en_US
dc.subject.other helium magnetostrictive low gravity lambda-transition thermal conductivity superconductive magnet heat current en_US
dc.title Thermal Conductivity Measurements of Helium 4 Near the Lambda-Transition Using a Magnetostrictive Low Gravity Simulator en_US


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