New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI
FOCUS is a direct-geometry cold neutron time-of-flight spectrometer at SINQ (PSI, CH). Its neutron guide was exchanged in 2019/2020 within the SINQ Upgrade project, while the rest of the instrument remained unchanged. The new guide provided a significant intensity increase across the whole spectrum,...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-02-01
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| Series: | Quantum Beam Science |
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| Online Access: | https://www.mdpi.com/2412-382X/8/1/8 |
| _version_ | 1797239537875812352 |
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| author | Fanni Juranyi Masako Yamada Christine Klauser Lothar Holitzner Uwe Filges |
| author_facet | Fanni Juranyi Masako Yamada Christine Klauser Lothar Holitzner Uwe Filges |
| author_sort | Fanni Juranyi |
| collection | DOAJ |
| description | FOCUS is a direct-geometry cold neutron time-of-flight spectrometer at SINQ (PSI, CH). Its neutron guide was exchanged in 2019/2020 within the SINQ Upgrade project, while the rest of the instrument remained unchanged. The new guide provided a significant intensity increase across the whole spectrum, especially at short wavelengths, due to the more efficient transport and extended phase space of the transported neutrons. The practically available energy transfer range (at the neutron energy loss side) was increased to about 40 meV. The main reason for the intensity benefit at short incident wavelengths was the improved guide coating, whereas at long wavelengths it was the new ballistic shape. The interesting part of the guide is the “peanut shape” of the curved part in the horizontal plane. For this, we derived the analytical restriction on the geometry to avoid a direct line of sight from the source. The guide geometry and the supermirror coating were optimized using Mcoptimize, a particle swarm optimization routine employing Mcstas. Future ballistic neutron guides may profit from the presented approaches, optimization strategy, and results. |
| first_indexed | 2024-04-24T17:53:07Z |
| format | Article |
| id | doaj.art-b7ad863ce4f04126a11547176513a848 |
| institution | Directory Open Access Journal |
| issn | 2412-382X |
| language | English |
| last_indexed | 2024-04-24T17:53:07Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Quantum Beam Science |
| spelling | doaj.art-b7ad863ce4f04126a11547176513a8482024-03-27T14:01:57ZengMDPI AGQuantum Beam Science2412-382X2024-02-0181810.3390/qubs8010008New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSIFanni Juranyi0Masako Yamada1Christine Klauser2Lothar Holitzner3Uwe Filges4Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 PSI Villigen, SwitzerlandLaboratory for Neutron and Muon Instrumentation, Paul Scherrer Institut, CH-5232 PSI Villigen, SwitzerlandLaboratory for Neutron and Muon Instrumentation, Paul Scherrer Institut, CH-5232 PSI Villigen, SwitzerlandLaboratory for Neutron and Muon Instrumentation, Paul Scherrer Institut, CH-5232 PSI Villigen, SwitzerlandLaboratory for Neutron and Muon Instrumentation, Paul Scherrer Institut, CH-5232 PSI Villigen, SwitzerlandFOCUS is a direct-geometry cold neutron time-of-flight spectrometer at SINQ (PSI, CH). Its neutron guide was exchanged in 2019/2020 within the SINQ Upgrade project, while the rest of the instrument remained unchanged. The new guide provided a significant intensity increase across the whole spectrum, especially at short wavelengths, due to the more efficient transport and extended phase space of the transported neutrons. The practically available energy transfer range (at the neutron energy loss side) was increased to about 40 meV. The main reason for the intensity benefit at short incident wavelengths was the improved guide coating, whereas at long wavelengths it was the new ballistic shape. The interesting part of the guide is the “peanut shape” of the curved part in the horizontal plane. For this, we derived the analytical restriction on the geometry to avoid a direct line of sight from the source. The guide geometry and the supermirror coating were optimized using Mcoptimize, a particle swarm optimization routine employing Mcstas. Future ballistic neutron guides may profit from the presented approaches, optimization strategy, and results.https://www.mdpi.com/2412-382X/8/1/8neutron guideballistic guidegeneralized direct line-of-sight conditionparticle swarm optimizationMcstasneutron spectrometer |
| spellingShingle | Fanni Juranyi Masako Yamada Christine Klauser Lothar Holitzner Uwe Filges New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI Quantum Beam Science neutron guide ballistic guide generalized direct line-of-sight condition particle swarm optimization Mcstas neutron spectrometer |
| title | New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI |
| title_full | New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI |
| title_fullStr | New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI |
| title_full_unstemmed | New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI |
| title_short | New Ballistic Neutron Guide for the Time-of-Flight Spectrometer FOCUS at PSI |
| title_sort | new ballistic neutron guide for the time of flight spectrometer focus at psi |
| topic | neutron guide ballistic guide generalized direct line-of-sight condition particle swarm optimization Mcstas neutron spectrometer |
| url | https://www.mdpi.com/2412-382X/8/1/8 |
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