Neutron velocity distribution from a superthermal solid 2H2 ultracold neutron source

I. Altarev; M. Daum; A. Frei; E. Gutsmiedl; G. Hampel; F. J. Hartmann; W. Heil; A. Knecht; J. V. Kratz; T. Lauer; M. Meier; S. Paul; U. Schmidt; Y. Sobolev; N. Wiehl; G. Zsigmond

doi:10.1140/epja/i2008-10604-8

2021 Impact factor 3.131

Hadrons and Nuclei

Eur. Phys. J. A (2008) 37: 9-14
https://doi.org/10.1140/epja/i2008-10604-8

Regular Article — Experimental Physics

Neutron velocity distribution from a superthermal solid ²H₂ ultracold neutron source

I. Altarev³, M. Daum⁴^*, A. Frei³, E. Gutsmiedl³, G. Hampel¹, F. J. Hartmann³, W. Heil², A. Knecht⁴^,6, J. V. Kratz¹, T. Lauer¹, M. Meier⁴, S. Paul³, U. Schmidt⁵, Y. Sobolev¹^,7, N. Wiehl¹ and G. Zsigmond⁴

¹ Institut für Kernchemie, Johannes Gutenberg-Universität, Fritz-Strassmann-Weg 2, D-55128, Mainz, Germany
² Institut für Physik, Johannes Gutenberg-Universität, Staudingerweg 7, D-55128, Mainz, Germany
³ Physik-Department, Technische Universität München, James-Franck-Strasse, D-85748, Garching, Germany
⁴ PSI, Paul Scherrer Institut, CH 5232, Villigen PSI, Switzerland
⁵ Physikalisches Institut, Ruprecht-Karls-Universität, Heidelberg, Germany
⁶ Physics Department, University Zürich, Zürich, Switzerland
⁷ Petersburg Nuclear Physics Institute, Gatchina, Russia

^* e-mail: manfred.daum@psi.ch

Received: 3 March 2008
Revised: 21 May 2008
Published online: 7 July 2008

Abstract

We have determined for the first time the velocity distribution of neutrons from a solid ²H₂ ultracold neutron (UCN) source. The spectrum rises sharply above 4.5m/s and has a maximum around 7m/s after transport in an 8m long guide. The number of neutrons in the UCN velocity range (< 7m/s) may be increased by a factor of two by placing the experiment 1m above the UCN source level.

PACS: 29.25.Dz Neutron sources – / 28.20.Gd Neutron transport: diffusion and moderation –

© SIF, Springer-Verlag Berlin Heidelberg, 2008