Optimal shape of a cold-neutron triple-axis spectrometer
(2011) International Workshop on Neutron Optics 634. p.1-6- Abstract
- We have performed a McStas optimization of the primary spectrometer for a generic 40 m long, cold-neutron triple-axis spectrometer with a doubly focusing monochromator. The optimal design contains an elliptically focusing guide, a virtual source point before a low-grade PG monochromator, and non-equidistant focusing at the monochromator. The flux at 5 meV shows a gain factor 12 over the "classical" design with a straight 12 x 3 cm(2), m=2 guide and a vertically focusing PG monochromator. In addition, the energy resolution was found to be improved. This unexpectedly large design improvement agrees with the Liouville theorem and can be understood as the product of many smaller gain factors, combined with a more optimal utilization of the... (More)
- We have performed a McStas optimization of the primary spectrometer for a generic 40 m long, cold-neutron triple-axis spectrometer with a doubly focusing monochromator. The optimal design contains an elliptically focusing guide, a virtual source point before a low-grade PG monochromator, and non-equidistant focusing at the monochromator. The flux at 5 meV shows a gain factor 12 over the "classical" design with a straight 12 x 3 cm(2), m=2 guide and a vertically focusing PG monochromator. In addition, the energy resolution was found to be improved. This unexpectedly large design improvement agrees with the Liouville theorem and can be understood as the product of many smaller gain factors, combined with a more optimal utilization of the beam divergence within the guide. Our results may be relevant for a possible upgrade of a number of cold-neutron triple-axis spectrometers and for a possible triple-axis spectrometer at the European Spallation Source. (C) 2010 Elsevier B.V. All rights reserved. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1987652
- author
- Lefmann, Kim LU ; Filges, U. ; Treue, F. ; Kirkensgard, J. J. K. ; Plesner, B. ; Hansen, K. S. and Kleno, K. H.
- organization
- publishing date
- 2011
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- Neutron instrumentation, Triple-axis spectrometer, Ray-tracing, simulation
- host publication
- Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
- volume
- 634
- pages
- 1 - 6
- publisher
- Elsevier
- conference name
- International Workshop on Neutron Optics
- conference location
- Grenoble, France
- conference dates
- 2010-03-17 - 2010-03-19
- external identifiers
-
- wos:000290355100001
- scopus:79952987086
- ISSN
- 0168-9002
- DOI
- 10.1016/j.nima.2010.06.273
- language
- English
- LU publication?
- yes
- id
- f438352c-e524-4043-be16-87df50b694e5 (old id 1987652)
- date added to LUP
- 2016-04-01 14:43:06
- date last changed
- 2022-01-28 02:09:11
@inproceedings{f438352c-e524-4043-be16-87df50b694e5,
abstract = {{We have performed a McStas optimization of the primary spectrometer for a generic 40 m long, cold-neutron triple-axis spectrometer with a doubly focusing monochromator. The optimal design contains an elliptically focusing guide, a virtual source point before a low-grade PG monochromator, and non-equidistant focusing at the monochromator. The flux at 5 meV shows a gain factor 12 over the "classical" design with a straight 12 x 3 cm(2), m=2 guide and a vertically focusing PG monochromator. In addition, the energy resolution was found to be improved. This unexpectedly large design improvement agrees with the Liouville theorem and can be understood as the product of many smaller gain factors, combined with a more optimal utilization of the beam divergence within the guide. Our results may be relevant for a possible upgrade of a number of cold-neutron triple-axis spectrometers and for a possible triple-axis spectrometer at the European Spallation Source. (C) 2010 Elsevier B.V. All rights reserved.}},
author = {{Lefmann, Kim and Filges, U. and Treue, F. and Kirkensgard, J. J. K. and Plesner, B. and Hansen, K. S. and Kleno, K. H.}},
booktitle = {{Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}},
issn = {{0168-9002}},
keywords = {{Neutron instrumentation; Triple-axis spectrometer; Ray-tracing; simulation}},
language = {{eng}},
pages = {{1--6}},
publisher = {{Elsevier}},
title = {{Optimal shape of a cold-neutron triple-axis spectrometer}},
url = {{http://dx.doi.org/10.1016/j.nima.2010.06.273}},
doi = {{10.1016/j.nima.2010.06.273}},
volume = {{634}},
year = {{2011}},
}