2. Equipment

In France (1996), all spectrometers use neutrons delivered by the [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14] nuclear research reactors, listed in . The operating principle and performance of most of them are described below.

A neutron beam emerges from a channel drilled in the biological shielding of a reactor or spallation source, with a Maxwellian flux distribution per unit wavelength d Φ / d λ (figure 2 ).