Neutron instrument concepts for a high intensity moderator at the European spallation source.

ABSTRACT

In the course of the Horizon 2020 project HighNESS, a second moderator concept has been developed for the European Spallation Source, which complements the currently built moderator and is optimized for high intensity with a large viewable surface area. In this work we introduce conceptual designs for neutron instruments for condensed matter research designed to make optimal use of the capabilities of this moderator. The focus is on two concepts for small-angle neutron scattering and one neutron imaging instrument, which are intended to complement corresponding instruments that are already under construction at the European Spallation Source. One small-angle neutron scattering instrument concept resembles a conventional pinhole collimator geometry and aims to profit from the proposed second moderator by enabling to illuminate larger samples and providing particularly high resolution, drawing on a 30 m collimation and corresponding detector distance. A second small-angle neutron scattering instrument concept adopts nested mirror optics that enable to efficiently exploit the large moderator size and provide high resolution by focusing on the detector. The neutron imaging instrument concept is a typical pinhole instrument that can be found at continuous sources and draws on the corresponding strengths of high flux and large homogeneous fields-of-view, while still providing moderate wavelength resolution for advanced imaging methods.