Magnetic field induced temperature changes in cryogenic liquids: N2, Ar, and He4

✍ Scribed by H.H Sample; L.G Rubin

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 736 KB
• Volume: 18
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(78)90006-1

✦ Synopsis

Measurements of magnetic fieM-induced changes in hydrostatic head corrections are reported for columns of liquid N 2 and Ar at their normal boiling points and for liquid He 4 between 2. 15and 4.2.1(, in static magnetic fields to 15 7". The results for very high purity N 2 and Ar are in good agreement with calculations based on gas susceptibilities; diamagnetic coolings of-32 +-1.5 and-64 + 6 mK are observed for liquid N2 and Ar respectively, at 15 7". However, 02 contamination in amounts as small as O. 1 at % can drastically alter the observed temperature changes. The measurements on He 4 above 3 K are also in good agreement with calculations based on the diamagnetic gas susceptibility. Below 3 K, the results deviate from the calculation in a paramagnetic direction; just above the X-point, paramagnetic warmings of "~10 mK are observed for a field of 15 7".