Optimization of multi-channel neutron focusing guides for extreme sample environments

Summary, in English

In this work, we present and discuss simulation results for the design of multi-channel neutron focusing guides for extreme sample environments. A single focusing guide consists of any number of supermirror-coated curved outer channels surrounding a central channel. Furthermore, a guide is separated into two sections in order to allow for extension into a sample environment. The performance of a guide is evaluated through a Monte-Carlo ray tracing simulation which is further coupled to an optimization algorithm in order to find the best possible guide for a given situation. A number of population-based algorithms have been investigated for this purpose. These include particle-swarm optimization, artificial bee colony, and differential evolution. The performance of each algorithm and preliminary results of the design of a multi-channel neutron focusing guide using these methods are described. We found that a three-channel focusing guide offered the best performance, with a gain factor of 2.4 compared to no focusing guide, for the design scenario investigated in this work.

• Author: Douglas DiJulio; E. Lelievre-Berna; P. Courtois; Ken Andersen; Phillip Bentley
• Department/s: Nuclear physics; European Spallation Source ESS AB
• Publishing year: 2014
• Language: English
• Pages: 012006-012006
• Publication/Series: International Workshop on Neutron Optics and Detectors (NOP&D 2013) 2–5 July 2013, Munich, Germany
• Volume: 528
• Links: http://dx.doi.org/10.1088/1742-6596/528/1/012006
• Document type: Conference paper
• Publisher: IOP Publishing
• Topic: Natural Sciences; Physical Sciences
• Conference name: International Workshop on Neutron Optics and Detectors (NOP&D)
• Conference date: 2013-07-02 - 2013-07-05
• Conference place: Munich, Germany
• Status: Published
• ISBN/ISSN/Other: ISSN: 1742-6588; ISSN: 1742-6596