Sample Environment

Several sample-environment options are available for experiments at HODACA. Available configurations depend on the required temperature, magnetic field, sample geometry, and compatibility with the spectrometer.

For sample-environment equipment and configurations used with HODACA, see the document below.

General sample-environment information

Additional sample-environment equipment is maintained by the Neutron Science Laboratory, ISSP, including low-temperature, high-temperature, magnetic-field, and high-pressure equipment.

For specifications and general information, see the ISSP Neutron Science Laboratory Sample Environments page.

[ISSP NSL Sample Environments]

Important note for high-temperature measurements

For measurements using the cryofurnace, Cu sample plates are recommended. Al plates may deform at high temperatures.

Typical preparation and cool-down times

The times below are practical estimates based on experience at HODACA. Actual cooling times depend on the sample, sample holder, thermal contact, refrigerator condition, and other experimental conditions.

Please allow sufficient margin when planning low-temperature measurements.

4 K GM refrigerator

Evacuating the sample environment typically takes approximately 30 minutes.

Cooling from room temperature to near the base temperature typically requires approximately 2.5–3 hours.

Allow additional time if stable thermal equilibrium at the sample is important.

For warm-up and user-handover procedures, see End of Experiment.

3He refrigerator

A liquid-helium-free, sorption-pumped ³He refrigerator is available for measurements down to approximately 0.3 K.

Initial pumping typically requires approximately 30 minutes. Under good operating conditions, cooling to the lowest-temperature region takes approximately 17 hours, although it often takes longer in practice.

For this reason, the sample should normally be installed and the cool-down started approximately 24 hours before the planned low-temperature measurement.

For controller settings, condensation and recondensation procedures, and temperature-control methods, see:

[³He Refrigerator — Operation Guide]