Efficient polarization analysis for focusing neutron instruments

Abstract

Polarized neutrons are a powerful probe to investigate magnetism in condensed\nmatter on length scales from single atomic distances to micrometers. With the\nongoing advancement of neutron optics, that allow to transport beams with\nincreased divergence, the demands on neutron polarizes and analyzers have grown\nas well. The situation becomes especially challenging for new instruments at\npulsed sources, where a large wavelength band needs to be polarized to make\nefficient use of the time structure of the beam.\n Here we present a polarization analysis concept for highly focused neutron\nbeams that is based on transmission supermirrors that are bend in the shape of\nequiangular spirals. The method allows polarizations above 95\\% and good\ntransmission, without negative impact on other beam characteristics. An example\nof a compact polarizing device already tested on the AMOR reflectometer is\npresented as well as the concept for the next generation implementation of the\ntechnique that will be installed on the Estia instrument being build for the\nEuropean Spallation Source.\n