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General guide concepts for compact, high-brilliance neutron moderators

Journal Article · · Review of Scientific Instruments
DOI:https://doi.org/10.1063/5.0212920· OSTI ID:2397441
 [1]
  1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
+ Show Author Affiliations
The trend in neutron sciences is toward integrating compact, high-brightness moderators into new or upgraded facilities. Transporting neutrons from the source to the sample position with a phase-space distribution tailored to specific requirements is crucial to leverage high source brilliance. Here we have investigated four guide concepts using Monte Carlo ray tracing simulations: Montel beamline with nested Kirkpatrick–Baez mirrors, curved-tapered beamline with a bender and straight sections, straight-elliptical beamline, and curved-elliptical beamline. The straight-elliptical (curved-elliptical) beamline features two half-ellipse guides connected by a straight (non-straight) guide section. The neutron transport efficiency and phase space homogeneity have been quantitatively compared. Our results show that the straight-elliptical beamline performs best because of few neutron bounces on the guide surface with small reflection angles, minimizing flux loss. The Montel beamline provides the best spatial confinement of neutrons within the desired region; however, there is a high thermal-neutron loss due to large reflection angles. The curved-tapered beamline suffers from significant flux loss due to high bounces, and it shows a non-uniform angular distribution related to broad ranges of bounces and reflection angles. The non-straight guide section of the curved-elliptical beamline increases the phase space inhomogeneity, leading to a spatially non-uniform beam profile. The results apply to general neutron instruments that require transporting thermal and cold neutrons from a compact, high-brilliance moderator to the sample location with a moderate phase-space volume.
Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
2397441
Journal Information:
Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 7 Vol. 95; ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

References (23)

Acceptance diagrams for curved neutron guides journal May 1990
Transmission properties of short curved neutron guides: Part I. Acceptance diagram analysis and calculations journal February 1995
The use of neutron optical devices on beam-hole experiments on beam-hole experiments journal July 1963
Advanced geometries for ballistic neutron guides
  • Schanzer, Christian; Böni, Peter; Filges, Uwe
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 529, Issue 1-3 https://doi.org/10.1016/j.nima.2004.04.178
journal August 2004
Curved–straight neutron guide system with uniform spatial intensity distribution
  • Mildner, D. F. R.; Cook, J. C.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 592, Issue 3 https://doi.org/10.1016/j.nima.2008.04.049
journal July 2008
China Spallation Neutron Source: Design, R&D, and outlook
  • Wei, Jie; Chen, Hesheng; Chen, Yanwei
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 600, Issue 1 https://doi.org/10.1016/j.nima.2008.11.017
journal February 2009
Systematic performance study of common neutron guide geometries
  • Klenø, Kaspar Hewitt; Lieutenant, Klaus; Andersen, Ken H.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 696 https://doi.org/10.1016/j.nima.2012.08.027
journal December 2012
Tailoring phase-space in neutron beam extraction
  • Weichselbaumer, S.; Brandl, G.; Georgii, R.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 793 https://doi.org/10.1016/j.nima.2015.05.003
journal September 2015
Generic guide concepts for the European Spallation Source
  • Zendler, C.; Martin Rodriguez, D.; Bentley, P. M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 803 https://doi.org/10.1016/j.nima.2015.09.035
journal December 2015
MCViNE – An object oriented Monte Carlo neutron ray tracing simulation package
  • Lin, Jiao Y. Y.; Smith, Hillary L.; Granroth, Garrett E.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 810 https://doi.org/10.1016/j.nima.2015.11.118
journal February 2016
Design of the cold and thermal neutron moderators for the European Spallation Source
  • Zanini, L.; Andersen, K. H.; Batkov, K.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 925 https://doi.org/10.1016/j.nima.2019.01.003
journal May 2019
Performance of neutron guide systems for low energy accelerator-driven neutron facilities
  • Ma, Z.; Lieutenant, K.; Voigt, J.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 1009 https://doi.org/10.1016/j.nima.2021.165479
journal September 2021
The Spallation Neutron Source in Oak Ridge: A powerful tool for materials research journal November 2006
Neutron beam extraction and delivery at spallation neutron sources journal June 2000
SciPy 1.0: fundamental algorithms for scientific computing in Python journal February 2020
Optimizing moderator dimensions for neutron scattering at the spallation neutron source journal December 2013
Conceptual moderator studies for the Spallation Neutron Source short-pulse second target station journal June 2016
PIONEER, a high-resolution single-crystal polarized neutron diffractometer journal July 2022
The raison d'être of long pulse spallation sources journal November 1997
The European Spallation Source Design journal December 2017
Optimization of moderators and beam extraction at the ESS journal March 2018
McStas: Past, present and future journal January 2014
Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex I: Pulsed Spallation Neutron Source journal August 2017

Figures / Tables (13)

FIG. 1(p. 4)figure FIG. 1
FIG. 2(p. 9)figure FIG. 2
FIG. 3(p. 11)figure FIG. 3
FIG. 4(p. 13)figure FIG. 4
FIG. 5(p. 14)figure FIG. 5
FIG. 6(p. 14)figure FIG. 6
FIG. 7(p. 15)figure FIG. 7
FIG. 8(p. 15)figure FIG. 8
FIG. 9(p. 17)figure FIG. 9
FIG. 10(p. 19)figure FIG. 10
FIG. S1(p. 27)figure FIG. S1
FIG. S2(p. 28)figure FIG. S2
FIG. S3(p. 29)figure FIG. S3

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