Sample Environment of the POWGEN Instrument

Sample Holders

Various different sample holders are used for the sample environment mentioned above. For detailed information about materials, dimensions and photos, please refer to the following document, called Powgen sample cans.

Powgen Automatic Changer

The Powgen Automatic Changer (PAC) is the second generation sample changer that was developed for POWGEN. The changer has a carousel that holds a maximum of 24 sample-filled vanadium cans and collects data in a temperature range of 10 to 300 K.

The cool down temperature from room temperature to 10 K is 45 minutes. However, samples can be changed at 10 K, which takes about 20 minutes.

ILL Furnace

The traditional ILL furnace built with vanadium heating elements is available for high-temperature measurements from room temperature to 1200°C. Cooling to 200°C takes 3-4 hours from highest temperature, and the remainder can be sped up in less than 30 minutes using exchange gas. The vacuum level of the furnace is ~2 x 10-5 torr. The aluminum tail of the furnace has been modified to have vanadium window for the primary beam.

ILL furnace can also be configured to have a quartz insert that allows flow of various gas mixtures through the sample using the gas handling system. The sample is loaded in a quartz basket with frit at the bottom and an open top for easy flow of gas through the sample. The furnace is capable of heating up to 850°C with this insert.

Orange Cryostat

This is a standard 50 mm bore orange cryostat with modified tails similar to the ILL furnace to eliminate aluminum in the path of the primary neutron beam. Temperature range is 2 to 300 K.

Cryo-Furnace (JANIS)

This is a top loading CCR which has two sticks. The cold stick has a temperature range of 5K-500K and the hot stick can go from 30K-650K PAC cans shown above are used with the cold stick. The hot stick uses ILL furnace cans..

Slim Sam (5T Magnet)

Slim Sam is a 5T vertical magnet with a cryo-stick that can go down to 2K. However, this has a Al VTI in the path of the primary beam and hence has a substantial background of Al peaks. Please see the power point slide for information about feasibility of using the magnet at powgen. Users are also strongly encouraged to discuss with instrument staff before requesting the magnet for their proposals.