Filling up the spin filter with polarised helium-3

The short film shown here was recorded during the historical experiment of 1996 [1] when the first spin filter was produced and then tested on the ILL neutron diffractometer D3.
(file formats: .mp4 (mp4 - 59 Mi), .webm (webm - 115 Mi))

See how anxious the experimental team is while preparing the very first spin filter bottle prior its installation on the instrument.

W. Heil (left) and H. Humblot (middle) working on the ³He polariser.
A series of cells are filled with 0.7 mbar of pure ³He atoms. The discharge applied in the cells put the ³He atoms in a metastable state. A laser light, circularly polarised with its axis parallel to the applied magnetic field, pump the gas and the obtained electronic polarisation is partially transferred to the nuclei through a hyperfine interaction. When enough nuclear-spins have been polarised, the ³He gas is then compressed in a two-stage non-magnetic titanium compressor. We see H. Humblot adjusting the assembly.
The neutron-spin filter cell is removed from the compressor by W. Heil once filled with the polarised gas under a pressure of several atmospheres. The polarisation remains for a long duration inside the bottle. With the help of T. Roberts, he puts the cell in a special container to transport it to D3 without loss of polarisation.
W. Heil and H. Humblot carry the filter to the ILL reactor hall, where A. Leadbetter (ILL Director) is anxiously waiting for them at D3.
F. Tasset, H. Humblot and W. Heil install the ³He spin filter cell inside the Cryopad-II in which they had trapped a magnetic field (Meissner effect). At the time, they had no better magnetostatic cavity for maintaining the ³He polarisation for long times..
F. Tasset is looking at the ratemeter to get a first estimate of the neutron-beam polarisation.

Reference
1- H. Humblot, W. Heil, E. Lelièvre-Berna & F. Tasset, Neutron News 8 (1997) 27. DOI: 10.1080/10448639708231997