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Neutrons for Science
able to work at night and weekends. In addition the scientists very quickly acquired excellent computer skills, including at the system level, allowing them to discuss these matters with the professionals on equal footing. The choices made reflected the users rather than the informatics specialists who usually directed laboratory mainframe systems at this time
5.3.3 Electronics and detectors
This was the domain of Anton Axmann who arrived at the ILL on 1 July 1969. He had experience with both electronics and physics, and had worked in industry, but also with Tasso Springer at Jülich. This background made him an ideal candidate to take charge of electronics at the ILL.
Detectors comprised a considerable part of the electronics. Neutrons being electrically neutral particles cannot be detected directly. First they must undergo a nuclear reaction which produces charged particles which are then detected. The reactions most often used are those following neutron absorption by boron-10 (usually in gaseous form as BF3), helium-3, lithium-6
or gadolinium. This is not the place to explain all the variants of detector construction. I will simply say that, in many experiments, there are great advantages in simultaneous collection of neutrons scattered at different angles86. A specific case is small angle
86 2018 addition: The main actors involved this field included Jean Jacobé (1967, engineer), André Rambaud (1969, technician), Pierre Convert (1970, scientist) and Dominique Feltin (joined the team in 1982). The group did an excellent job and played a key role in the advent and popularisation of neutron multi-detectors (also called Position Sensitive Detectors), which can be either one dimensional and curved (so-called “banana” de- tectors) or two dimensional. With the development of ever bigger and more efficient multi-detectors over the years, these components rapidly became a standard feature of the majority of neutron spectrometers both at the ILL and around the world. The original patent dates back to 1968 (see FR148589A or US3614437A).
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