3He melting curve thermometry in a nuclear polarization experiment

Temperature measurement and control are important in brute force polarization experiments. We discuss the installation and use of³He melting curve thermometers in a crystat used to polarize a TiH2 target. Comparison is made between the melting curve thermometers and the⁶⁰CoCo nuclear orientation thermometer, which is often used in such experiments. The melting curve thermometers provide increased temperature resolution and sensitivity, and were used in a feedback heating system to control temperature to ±5.5 μK at 16.5 mK. The³He melting curve and the⁶⁰CoCo temperature scales are found to agree within 2% at 15 mK. The present status of the melting curve scale and the effect of a magnetic field on melting curve thermometry are also discussed. © 1992 J.C. Baltzer A.G., Scientific Publishing Company.

Duke Scholars

Author Werner Tornow Physics