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D10

Four-circle diffractometer with three-axis energy analysis

The trick of the advanced dilution cryostat of D10

A neutron radiograph film recorded at the ILL in 2005 on NEUTROGRAPH shows the progressive dilution of helium-3 into helium-4 inside a capillary which is at the heart of ultra-low temperature space cryostats. Such an in situ observations is possible only using neutrons where there is a marked isotopic effect for helium (helium-4 is transparent, helium-3 is opaque to neutrons).

Ref.: M. Enderle, S. Pujol, A. Hillenbach (Institut Laue-Langevin), A. Benoit (CRTBT CNRS) (2005) communication privée.