抄録
The triple point of neon is realized calorimetrically using a closed cycle refrigerator (a Gifford-McMahon type refrigerator). The usage of the closed cycle refrigerator combined with a closed fixed-point cell is found not only to be the easiest and the simplest way to realize the fixed points in both handling and operation compared with the traditional cryogenic technique using liquid helium, but to have a potential to be one of the most accurate realizing methods. The standard uncertainty of this system in calibrating standard platinum resistance thermometers at the triple point of natural neon is estimated to be 0.056mK. The highly stable low temperature environment of the refrigerator revealed that natural neon has long relaxation time constants for the isotopic spatial equilibration after pulse heating.
