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Thermometric Fixed Points Using Superconductivity

  • J. F. Schooley
  • R. J. SoulenJr.
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 17)

Abstract

In current practice, precision in thermometry below 20°K is commonly achieved by measuring the vapor pressure of liquid helium or by the use of resistive or paramagnetic thermometers. The latter techniques provide a wider temperature range than the 0.3 to 4°K range over which combination of He3 and He4 vapor pressure bulbs can be used, but both the resistive and the paramagnetic thermometers must be recalibrated continually against the vapor pressure scale (or a similarly dependable primary thermometer) to assure continued accuracy. Considerable effort is involved in the recalibration process, particularly in experiments involving the use of the He3–He4 dilution refrigerator; in this case, the refrigerant is a mixture of He3 and He4, which cannot be used directly as a thermometric medium. Moreover, it is difficult to attach and to use a separate vapor pressure bulb in this apparatus, since the experiment is often connected to the dilution chamber by an imperfect thermal link.

Keywords

Mutual Inductance Electrical Lead Helmholtz Coil Paramagnetic Salt Thermometer Temperature 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    J. P. Franck and D. L. Martin, Can. J. Phys., 39: 1320 (1961).CrossRefGoogle Scholar
  2. 2.
    J. E. Neighbor, J. F. Cochran, and C. A. Shiffman, in: Proc. IXth Int. Conf on Low Temperature Physics, Springer Science+Business Media New York (1965), p. 479.Google Scholar
  3. 3.
    W. D. Gregory, Phys. Rev., 165: 556 (1968).Google Scholar
  4. 4.
    J. H. Colwell, J. F. Schooley, and R. J. Soulen, Jr., J. Appl. Phys., 40: 2163 (1969).Google Scholar
  5. 5.
    J. F. Schooley and R. J. Soulen, Jr., paper 9Ta9, presented at 12th Int. Conf. on Low Temperature Physics, Kyoto, Japan, Sept. 4–10, 1970.Google Scholar
  6. 6.
    J. Clarke, in: Proc. of the Symposium on the Physics of Superconducting Devices,University of Virginia, Charlottesville, Virginia (Apr. 28–29, 1967), paper D-1.Google Scholar
  7. 7.
    P. Sullivan and G. Seidal, Ann. Acad. Sci. Fenn. Physica, Ser. A VI, 210: 58 (1966).Google Scholar
  8. 8.
    R. J. Soulen, Jr. and J. H. Colwell, J. Low Temp. Phys., 5: 325 (1971).Google Scholar
  9. 9.
    J. E. Kunzler, R. H. Geballe, and G. W. Hull, Jr., in: Temperature, Its Measurement and Control in Science and Industry, Vol. 3, part 1, Reinhold, New York (1962), p. 391. (Many other workers have examined these thermometers; for example, see H. H. Plumb and G. Cataland, J. Res. NBS, 69A:375 (1965).Google Scholar
  10. 10.
    H. Plumb and G. Cataland, Metrologia, 2: 127 (1966).CrossRefGoogle Scholar
  11. 11.
    R. H. Sherman, S. G. Sydoriak, and T. R. Roberts, J. Res. NBS, 68A: 579 (1964).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1972

Authors and Affiliations

  • J. F. Schooley
    • 1
  • R. J. SoulenJr.
    • 1
  1. 1.National Bureau of StandardsUSA

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