Nuclear Physics Methods in Materials Research

The present European success in neutron physics and in neutron scattering applied to condensed matter research rests upon the subtle interaction of new instrument requirements for an expanding scientific program in Physics, Chemistry and Biology and the programme of invention of neutron instruments, which has long been a characteristic of neutron physics, particularly in Germany. Although this distinction between the role played by the instrument demands of "problem oriented" scientists and the interest of "instrument inventors" is somewhat facile, I believe it to be worthwhile since progress needs both components; many of the uses of a new method only becoming evident as it is improved under the conditions of real experiment. The Institut Laue Langevin in Grenoble brings both streams together and a measure of its importance on the or1d scene can be seen in Figure 1, which charts the world publications in Neutron Physics and Neutron Scattering since the neutron's discovery. This figure also clearly shows the correlation between innovation (and publication) in neutron science and the flux of neutrons available. hi1st in 1936 it was possible to demonstrate the wave properties and diffraction of neutrons(1)(2) it was not until 1944 with the "pile" CP3 at Argonne National Laboratory that intensities were high enough to stimulate the construction of the first neutron diffractometer and development 22 c 900 A_ UJ DIDO, SACLAY, GARCHING LL en WORLD TOTAL::: i 700 m ORRR, NRU, NlO:: B_ LL. L.::: J PLUTO x LO -, !: !: a.