Development of high intensity neutron source at the European Spallation Source

Issue title: ICANS-XXIII, hosted by the Oak Ridge National Laboratory Neutron Sciences Directorate

Guest editors: Kenneth W. Herwig and Erik B. Iverson

Article type: Research Article

Authors: Santoro, V.^{a; b; *} | Andersen, K.H.^a | DiJulio, D.D.^{a; b} | Klinkby, E.B.^c | Miller, T.M.^a | Milstead, D.^d | Muhrer, G.^a | Strobl, M.^e | Takibayev, A.^a | Zanini, L.^a | Zimmer, O.^f

Affiliations: [a] European Spallation Source ERIC, P.O. Box 176, 22100 Lund, Sweden | [b] Department of Physics, Lund University, 22100 Lund, Sweden | [c] DTU Nutech, Technical University of Denmark, DTU Risø Campus, Frederiksborgvej 399, DK-4000, Roskilde, Denmark | [d] Stockholm University, SE-106 91 Stockholm, Sweden | [e] Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen, Switzerland | [f] Institut Laue-Langevin, 38042 Grenoble, France

Correspondence: [*] Corresponding author. E-mail: valentina.santoro@esss.se.

Abstract: The European Spallation Source being constructed in Lund, Sweden will provide the user community with a neutron source of unprecedented brightness. By 2025, a suite of 15 instruments will be served by a high-brightness moderator system placed above the spallation target. The ESS infrastructure, consisting of the proton linac, the target station, and the instrument halls, allows for implementation of a second source below the spallation target. We propose to develop a second neutron source with a high-intensity moderator able to (1) deliver a larger total cold neutron flux, (2) provide high intensities at longer wavelengths in the spectral regions of Cold (4–10 Å), Very Cold (10–40 Å), and Ultra Cold (several 100 Å) neutrons, as opposed to Thermal and Cold neutrons delivered by the top moderator. Offering both unprecedented brilliance, flux, and spectral range in a single facility, this upgrade will make ESS the most versatile neutron source in the world and will further strengthen the leadership of Europe in neutron science. The new source will boost several areas of condensed matter research such as imaging and spin-echo, and will provide outstanding opportunities in fundamental physics investigations of the laws of nature at a precision unattainable anywhere else. At the heart of the proposed system is a volumetric liquid deuterium moderator. Based on proven technology, its performance will be optimized in a detailed engineering study. This moderator will be complemented by secondary sources to provide intense beams of Very- and Ultra-Cold Neutrons.

Keywords: Moderator, neutrons, source, ESS, ultra cold neutron, very cold neutron

DOI: 10.3233/JNR-200159

Journal: Journal of Neutron Research, vol. 22, no. 2-3, pp. 209-219, 2020