Physica B 356 (2005) 103–108 First results from Tyrex, the new polarized- 3 He filling station at ILL K.H. Andersen à , R. Chung, V. Guillard, H. Humblot, D. Jullien, E. Lelie`vre-Berna, A. Petoukhov, F. Tasset Institut Laue-Langevin, 6, rue J. Horowitz, F-38042 Grenoble Cedex 9, France Abstract A new filling station for nuclear polarisation of 3 He gas has been constructed at the ILL, Grenoble. The ‘‘Tyrex’’ machine uses metastability-exchange optical pumping for polarising the 3 He gas at about 1mbar pressure. The gas is then compressed up to several bars via a hydraulic titanium-alloy piston compressor. The machine can provide about 1.5bar-l/h of polarised gas—an order-of-magnitude increase over the first filling station installed at the ILL in 1996. The compressed, polarised gas is used for polarising neutron beams for condensed-matter and fundamental physics experiments. First results are presented and examples of implementations on existing neutron instruments at ILL are described. r 2004 Elsevier B.V. All rights reserved. PACS: 61.12.Ex; 61.12.Ld; 29.30.Hs Keywords: Metastability-exchange optical pumping; Neutron spin filter; Polarised neutron scattering 1. Introduction The Institut Laue-Langevin traditionally has a strong record in the use of polarised neutron techniques for condensed-matter investigations [1–4]. With the advent of polarised- 3 Heasaviable technique for neutron-beam polarisation, a filling station for polarised- 3 He gas was installed at ILL in1996incollaborationwithMainzUniversity [5]. This was based on an LNA laser coupled to a double-stage twin piston compressor, developed at Mainz. The facility provides 55% nuclear-spin polarisation in cells of up to 5bars pressure at a production rate of about 0.3bar-l/h. In order to improve on this performance, a new device was proposed, which was funded jointly by the British partner of the ILL (EPSRC), an RTD contract within EC-FP5 (ENPI) coordinated by ILL, and the CEA-Grenoble. The new filling station has been nicknamed Tyrex. ARTICLE IN PRESS www.elsevier.com/locate/physb 0921-4526/$-see front matter r 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.physb.2004.10.057 à Corresponding author. Tel.: +33476207137. E-mail address: andersen@ill.fr (K.H. Andersen).