Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT

P. Schmidt-Wellenburg; K. H. Andersen; P. Courtois; M. Kreuz; S. Mironov; V. V. Nesvizhevsky; G. Pignol; K. V. Protasov; T. Soldner; F. Vezzu; O. Zimmer

doi:10.1016/j.nima.2009.07.096

arXiv · 0811.1635

Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT

P. Schmidt-Wellenburg·K. H. Andersen·P. Courtois·M. Kreuz·S. Mironov·V. V. Nesvizhevsky·G. Pignol·K. V. Protasov·T. Soldner·F. Vezzu·O. Zimmer

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Abstract

The gravitational spectrometer GRANIT will be set up at the Institut Laue Langevin. It will profit from the high ultracold neutron density produced by a dedicated source. A monochromator made of crystals from graphite intercalated with potassium will provide a neutron beam with 0.89 nm incident on the source. The source employs superthermal conversion of cold neutrons in superfluid helium, in a vessel made from BeO ceramics with Be windows. A special extraction technique has been tested which feeds the spectrometer only with neutrons with a vertical velocity component v < 20 cm/s, thus keeping the density in the source high. This new source is expected to provide a density of up to 800 1/cm3 for the spectrometer.

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P. Schmidt-Wellenburg, K. H. Andersen, P. Courtois, M. Kreuz, S. Mironov, V. V. Nesvizhevsky, G. Pignol, K. V. Protasov, T. Soldner, F. Vezzu, O. Zimmer. 2008-11-11. Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT. https://doi.org/10.1016/j.nima.2009.07.096

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