THE LONG-WAVELENGTH NEUTRON SPIN-ECHO SPECTROMETER IN15 AT THE INSTITUT LAUE-LANGEVIN

A new ultra-high resolution neutron spin-echo spectrometer at the ILL (Grenoble) extends the time range for measurements of the intermediate scattering function S(Q,t) far beyond what has previously been possib le. The spectrometer design is traditional, utilizing long neutron wav elengths (8-25 Angstrom) and large, homogeneous precession coils to re ach Fourier times approaching the microsecond. The standard operationa l mode is currently functional, providing a Fourier time range of 0.03 -180 ns, and a momentum transfer between 0.01 and 0.2 Angstrom(-1). Th e other two operational modes (neutron optical focusing and time of fl ight) are also discussed. (C) 1998 Elsevier Science B.V. All rights re served.