Curved crystal optics and the resolution formalism: programs and optimization procedures

Abstract The problem of computing the neutron optics of curved-crystal spectrometers is reviewed. The conditions of focusing in scattering and the limitations to achievable resolutions are discussed. Experience with programs for resolution-intensity optimization is presented. Computational examples are given of high resolution configurations with bent crystals and open beams, showing significant intensity gain over conventional techniques. Quasi-elastic scattering measurements at energy transfer resolutions below 10 μeV are shown to be feasible at high luminosity. Curved monochromators for high resolution neutron powder diffraction, combining the beam focusing onto sample with focusing in scattering, are also discussed.

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