Neutron guide-split: A high performance guide bundle concept for elliptical guides

Using ray-tracing simulations of three different set-ups (with two, four, and eight secondary guides) we show that it is possible to illuminate at least eight sample positions from one beam port with a brilliance transfer above 90% on each sample on a 150 m long instrument. This has been done for a phase space volume comprised of an area of 1×1 cm2 and a maximum divergence of±0.5° within a wavelength band of 4.25-5.75 Å. We show, by a full virtual experiment, an example of applying the guide-split concept to an instrument proposed for the European Spallation Source, namely a magnetism diffractometer.