| Autor: |
Michael Monkenbusch, Karl Zeitelhack, Gunther Borchert, C. Breunig, Olaf Holderer |
| Rok vydání: |
2008 |
| Předmět: |
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| Zdroj: |
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 586:90-94 |
| ISSN: |
0168-9002 |
| DOI: |
10.1016/j.nima.2007.11.038 |
| Popis: |
The neutron spin-echo instrument, J-NSE, that has been moved from the ELLA guide hall at the FRJ-2 in Julich to the guide hall of the new FRM II reactor, needs an intense beam of polarized neutrons. Polarization of the short wavelengths is achieved in a bent section of about 8 m and radius 160 m, with a m = 3 FeSi multilayer coating. Due to the total reflection of FeSi, longer wavelengths ( λ ≃ 10 – 20 A ) pass unpolarized and need an additional short polarizer at the entrance of the instrument. After the bent section within a 10 m straight guide section a turn of vertical polarization to longitudinal guide field is performed and a selector is inserted. Then about 10 m of tapered 58Ni covered guide follows, which end with a cross-section of 60 × 60 mm 2 . We present the design criteria and first measurements on the performance of this guide concept. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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Full Text from ScienceDirect