The 30 m Small-Angle Neutron Scattering Instruments at the National Institute of Standards and Technology

Abstract

Two high‐resolution, general‐purpose, small‐angle neutron scattering instruments have been constructed at the National Institute of Standards and Technology's Center for Neutron Research. The instruments are 30 m long and utilize mechanical velocity selectors, pinhole collimation and high‐data‐rate two‐dimensional position‐sensitive neutron detectors. The incident wavelength, wavelength resolution and effective length of the instruments are independently variable, under computer control, and provide considerable flexibility in optimizing beam intensity and resolution. The measurement range of the instruments extends from 0.0015 to 0.6 Å−1 in scattering wavevector, corresponding to structure in materials from 10 Å to nearly 4000 Å. The design and characteristics of the instruments, and their modes of operation, are described, and data are presented which demonstrate their performance.

A comparative study of the structure–property behavior of highly branched segmented poly(urethane urea) copolymers and their linear analogs

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Conformation of Arborescent Polymers in Solution by Small-Angle Neutron Scattering: Segment Density and Core−Shell Morphology

“…12,13 The raw data were corrected for scattering from the empty cell, detector dark current, detector sensitivity, sample transmission, and thickness. After these corrections, the data were placed on an absolute scale using either a calibrated secondary standard or direct beam measurement and circularly averaged to produce I(q) versus q plots where I(q) is the scattered intensity and q ) sin(θ)4π/λ is the scattering vector for a scattering angle θ.…”

Assessment of detector calibration materials for SANS experiments

“…They can also be used to place results on an absolute scale. This has been described in reviews by Wignall & Bates (1987), Russell et al (1988) and Glinka et al (1998).…”