The Boiling Points and Triple Points of Oxygen and Argon

Abstract
The boiling point and triple point of pure oxygen have been realized with a reproducibility of ±0.2 and ±0.1 mK respectively. These realizations have been used to determine the temperatures of the boiling point of argon as 87.2941 K and the triple point of argon as 83.7974 K. The reproducibility of these determinations was ±0.2 mK. These results are in close agreement with other recent determinations and support the adoption of the triple point of argon as an alternative fixed point on the IPTS 68 to the boiling point of oxygen. This close agreement indicates that, because of the quite different methods used in all the determinations, it is unlikely that gross systematic errors exist.