Time-of-Flight Diffractometer Developed for Biological Small-Angle Scattering at Argonne’s Intense Pulsed Neutron Source, IPNS-I

A method of time-of-flight, small-angle neutron scattering (TOF-SANS) has been developed based on the iMATERIA powder diffractometer at BL20, of the Materials and Life Sciences Facility (MLF) at the high-intensity proton accelerator (J-PARC). A large-area detector for SANS, which is composed of triple-layered 3He tube detectors, has a hole at its center in order to release a direct beam behind and to detect ultra-small-angle scattering. As a result, the pulsed-neutron TOF method enables us to perform multiscale observations covering 0.003 < q (Å−1) < 40 (qmax/qmix = 1.3 × 104) and to determine the static structure factor S(q) and/or form factor P(q) under real-time and in-situ conditions. Our challenge, using unique sample accessories of a super-conducting magnet and polarized neutron, is dynamic nuclear polarization (DNP) for contrast variation, especially for industrial use. To reinforce conventional SANS measurements with powder materials, grazing-incidence small-angle neutron scattering (GISANS) or reflectivity is also available on the iMATERIA instrument.

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Tests of modulated intensity small angle scattering in time of flight mode

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2011.11.075 ◽

2012 ◽

Vol 667 ◽

pp. 1-4 ◽

Cited By ~ 8

Author(s):

G. Brandl ◽

J. Lal ◽

J. Carpenter ◽

L. Crow ◽

L. Robertson ◽

...

Keyword(s):

Small Angle ◽

Time Of Flight ◽

Small Angle Scattering ◽

Flight Mode ◽

Angle Scattering

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A new time-of-flight small-angle scattering instrument at the Helmholtz-Zentrum Berlin: V16/VSANS

Journal of Applied Crystallography ◽

10.1107/s1600576713030227 ◽

2014 ◽

Vol 47 (1) ◽

pp. 237-244 ◽

Cited By ~ 20

Author(s):

Karsten Vogtt ◽

Miriam Siebenbürger ◽

Daniel Clemens ◽

Christian Rabe ◽

Peter Lindner ◽

...

Keyword(s):

Momentum Transfer ◽

Small Angle ◽

Soft Matter ◽

Scattering Length ◽

Time Of Flight ◽

Small Angle Scattering ◽

Neutron Guide ◽

Macromolecular Assemblies ◽

Angle Scattering ◽

The Individual

Small-angle scattering methods have become routine techniques for the structural characterization of macromolecules and macromolecular assemblies like polymers, (block) copolymers or micelles in the spatial range from a few to hundreds of nanometres. Neutrons are valuable scattering probes, because they offer freedom with respect to scattering length density contrast and isotopic labelling of samples. In order to gain maximum benefit from the allotted experiment time, the instrumental setup must be optimized in terms of statistics of scattered intensity, resolution and accessible range in momentum transferQ. The new small-angle neutron scattering instrument V16/VSANS at the Helmholtz-Zentrum in Berlin, Germany, augments neutron guide collimation and pinhole optics with time-of-flight data recording and flexible chopper configuration. Thus, the availableQrange and the respective instrumental resolution in the intermediate and high momentum transfer regions can be adjusted and balanced to the individual experimental requirements. This renders V16/VSANS a flexible and versatile instrument for soft-matter research.

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Resolution of time-of-flight small-angle neutron diffractometers

Journal of Applied Crystallography ◽

10.1107/s0021889887086679 ◽

1987 ◽

Vol 20 (4) ◽

pp. 273-279 ◽

Cited By ~ 7

Author(s):

R. P. Hjelm

Keyword(s):

Small Angle ◽

National Laboratory ◽

Argonne National Laboratory ◽

Time Of Flight ◽

Simple Method ◽

Neutron Diffractometer ◽

Reduction Methods ◽

Measurement Strategies ◽

Pulsed Neutron ◽

Pulsed Neutron Source

A simple method of calculating the resolution of small-angle neutron data from diffractometers which use time-of-flight techniques has been derived in terms of the variances of the time and spatial channels of the measurement. The method is used to calculate the resolution in scattering-vector space of scattering intensity from a simulated isotropic scatterer on the small-angle neutron diffractometer at the Intense Pulsed Neutron Source at Argonne National Laboratory. The effects of the various instrumental geometries, time-of-flight measurement strategies and data reduction methods that can be chosen by the experimenter are considered. It is found that the best resolution is obtained with weighted constant Δt/t time-of-flight data acquisition schemes, with the detector placed in the beam in such a way that the highest possible angular range is accessed.

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