Spin-echo small-angle neutron scattering, a real-space scattering technique – Niels Bohr Institute - University of Copenhagen

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Spin-echo small-angle neutron scattering, a real-space scattering technique

Wim G. Bouwman,
Delft University of Technology, The Netherlands

Conventional small-angle neutron scattering (SANS) yields information in reciprocal space, which is not convenient to explain to non-expert users of the technique. To obtain a high resolution one has to collimate the beam which leads to a loss in intensity. In Delft we have developed spin- echo small-angle neutron scattering (SESANS) that solves these two issues by the use of the Larmor precession of polarised neutrons in magnetic fields. It is an efficient method to measure structures in real space without the need to collimate the beam [1]. The technique is sensitive to structural features in the length range from 100 nm to 18 micrometers. As an illustration we show here the phase transition in a colloidal system as function of the volume fraction, from gas via liquid to solid, which directly can be identified from SESANS-measurements [2]. In the presentation several applications from the technique will be shown.

[1] Real-space neutron scattering methods, W.G. Bouwman, J. Plomp, V.O. de Haan, W.H. Kraan, A.A. van Well, K. Habicht, T. Keller, M.T. Rekveldt, Nuclear Instruments and Methods in Physics Research A 586 9-14 (2008)

[2] Structural transitions of hard-sphere colloids studied by spin-echo small-angle neutron scattering, T. Krouglov, W.G. Bouwman, J. Plomp, M. Th. Rekveldt, G.J. Vroege, A.V. Petukhov and D.M.E. Thies-Weesie, J. Appl. Cryst. 36, (2003) 1417-1423