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Characterization of a ballistic supermirror neutron guide

H. Abele·D. Dubbers·H. Haese·M. Klein·A. Knoepfler·M. Kreuz·T. Lauer·B. Maerkisch·D. Mund·V. Nesvizhevsky·A. Petoukhov·C. Schmidt·M. Schumann·T. Soldner
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Abstract

We describe the beam characteristics of the first ballistic supermirror neutron guide H113 that feeds the neutron user facility for particle physics PF1B of the Institute Laue-Langevin, Grenoble (ILL). At present, the neutron capture flux density of H113 at its 20x6cm2 exit window is 1.35x10^10/cm^2/s, and will soon be raised to above 2x10^10/cm^2/s. Beam divergence is no larger than beam divergence from a conventional Ni coated guide. A model is developed that permits rapid calculation of beam profiles and absolute event rates from such a beam. We propose a procedure that permits inter-comparability of the main features of beams emitted from ballistic or conventional neutron guides.

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H. Abele, D. Dubbers, H. Haese, M. Klein, A. Knoepfler, M. Kreuz, T. Lauer, B. Maerkisch, D. Mund, V. Nesvizhevsky, A. Petoukhov, C. Schmidt, M. Schumann, T. Soldner. 2005-10-26. Characterization of a ballistic supermirror neutron guide. https://doi.org/10.1016/j.nima.2006.03.020

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