SKADI

The Small-K Advanced DIffractometer (SKADI) [1,2] small-angle neutron scattering (SANS) instrument is under construction at the European Spallation Source (ESS) as an in-kind contribution led by Forschungszentrum Jülich (Germany) in collaboration with Laboratoire Léon Brillouin (France) [1,2]. The project will be completed in 2026 with the end of cold commissioning.

SKADI is a versatile SANS instrument, which will enable scientists to perform a wide range of investigations on topics requiring small scattering angles to access long length scales. The scientific areas targeted by SKADI include investigations of smart materials, biological and medical research, magnetic materials and materials for energy storage, as well as experiments on nanomaterials and nanocomposites or colloidal systems. These experiments promise a high potential impact on science and society. To maximize the societal applicability of these studies SKADI is designed to accommodate in-situ measurements with custom made sample environments to provide "real-world" conditions.

SKADI Overview Image with shielding removed (left) and current construction stage (right). Neutrons are passing through the instrument from the moderator (left), through the sample, to the detector (right).

All SKADI key components are designed to meet the goal of delivering the infrastructure for outstanding scientific experiments. The corresponding design decisions are flexibility of the sample area (3x3 m2, generic mounting system for custom made sample environments), access to very small scattering angles by using focusing elements (Q ≥ 10−4 Å−1, corresponding to a size resolution of several micrometers.), polarization for magnetic samples and incoherent background subtraction, excellent wavelength resolution, tune-able down to ∆λ/λ = 1% [3] and a high dynamic Q-range, covering three orders of magnitude for structural investigations from nanometers to micrometers.

Along with the SKADI construction we were able to secure third party funding for the development of a neutron detector within the Horizon 2020 framework of the EU (funding reference No. 654124). [4] The Solid State Neutron Detector (SoNDe) project focused on the development of a high-flux capable neutron detector for the application in neutron scattering instruments at spallation sources, such as the ESS. The SONDE project was successfully finished in 2019.[4]

Other third party fundings are concerned with sample environment and the capability for grazing incidence scattering for surface investigations.

The SKADI team, together with collaboration partners from TU München, TU Darmstadt and University of Bielefeld was able to secure funding for a quick sample environment changer (FlexiProb). There a system to exchange complex sample environments (in-situ vapour chambers, foaming setups and dynamic light scattering) in under an hour on a SANS instrument.[5] (Röntgen Ångström Call)

In order to increase the capabilities for surface investigation (Grazing Incidence Small-Angle Neutron Scattering, GISANS) the SKADI team partnered with the University Uppsala, LMU München and University of Malmö to develop a mirror system to increase the incoming angle for surface scattering. (Röntgen Ångström Call)

In concert these two projects will advance the capabilities for SANS and therefore allow advances in material analysis to be made on a world-class level. This progress in technological abilities will benefit a wide range of scientific fields from medical research to material sciences as mentioned above. As both projects are performed in collaboration with strong European partners (LLB, ESS), they also improve the international visibility and involvement of the JCNS in large-scale scientific facilities.

SKADI Team

Forschungszentrum Jülich (DE): Sebastian Jaksch, Henrich Frielinghaus, Tadeusz Kozielewski, Romuald Hanslik
Laboratoire Léon Brillouin (FR): Sylvain Désert

References and Links

[1]Jaksch, S.; Martin-Rodriguez, D.; Ostermann, A.; Jestin, J.; Pinto, S. D.; Bouwman, W.; Uher, J.; Engels, R.; Frielinghaus, H.,
Concept for a time-of-flight Small Angle Neutron Scattering instrument at the European Spallation Source.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2014, 762, 22-30.

[2] ESS website feature https://europeanspallationsource.se/instruments/skadi

[3]Jaksch, S.,
Considerations about chopper configuration at a time-of-flight SANS instrument at a spallation source.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2016, 835, 61-65.

[4] Jaksch, S., Engels, R., Kemmerling, G., Clemens, U., Désert, S., Perrey, H., ... & Al Jebali, R. (2018). Recent developments SoNDe high-flux detector project. In Proceedings of the International Conference on Neutron Optics (NOP2017) (p. 011019).

[5] Jaksch, S., Chennevière, A., Désert, S., Kozielewski, T., Feilbach, H., Lavie, P., ... & Müller-Buschbaum, P. (2021). Technical specification of the small-angle neutron scattering instrument SKADI at the European spallation source. Applied Sciences, 11(8), 3620.

Contact Information

Sebastian Jaksch