Page 139 - Neutrons for Sciences and Society

Chapter 5: The construction of the reactor and the scientific groups
scattering. In most cases this is achieved using two dimensional detectors where the electrode arrangement is used to locate the points of impact of the neutrons with a resolution of the order of 1 cm for gas detectors, and about a millimetre for detectors using a solid absorber.
Help from CENG/LETI, and in particular RobertAllemand from Roger Gariod’s group was vial for this development of these multidetectors.
5.3.4 Sample environment
A large fraction of experiments require the sample to be at high or low temperatures, possibly under pressure, or placed in a magnetic field. An advantage of neutrons over X-rays is the fact that they penetrate metal enclosures much more easily; this facilitates creat- ing a suitable environment when required by the experiment.
The first devices were made for low temperatures. Grenoble could offer excellent support in this field. I have already mentioned the CNRS low-temperature laboratory (CRTBT) directed by Louis Weil until his death in 1968. They had helped build the cold source at Saclay. Weil also led a low temperature group at the CENG. In addition Air Liquide had an outstation
at Fontaine, in the outskirts of Grenoble. Louis Weil and Albert Lacaze had created a company named TBT (Très Basses Températures) to exploit their expertise. This company had been taken over by Air Liquide. One of the very first recruits to the ILL was Gabriel Prati, a technician from TBT, in 1969, followed
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