Tyrex-2
Polarised helium-3 filling station
TYREX before TYREX-2
The “Tyrex” filling station for nuclear polarisation of 3He gas was constructed at the ILL during the period 2000-2002. The Tyrex machine uses metastability exchange optical pumping for polarising the 3He gas at about 1 mbar pressure. The gas is then compressed up to several bars via a hydraulic titanium-alloy piston compressor. The machine could provide about 1.3 bar.l/h of 75-80% polarised gas.
Image 1: Compressor
- Powerful hydraulic actuator under closed-loop computer control
- Velocity: 30 cm/sec, final position within 3 µm precision
- Polarisation Preserving Piston and Chamber: Titanium alloy, 11 cm diameter and 55 cm stroke
- Total displacement: 5200 cm3, compression ratio: > 15000
Image 2: Laser
- Infrared Yb-fiber laser (All-fiber V-Grove Tech.)
- Optimised for helium gas 23S1-23P transition (1083 nm, 2 GHz bandwidth)
- Power : 50W (five 10W units)
Image 3: Magnetic field
- 9 coils of 2 m diameter
- Field amplitude: 10 Gauss
- Homogeneity region: diameter 0.9 m, length 2.5 m
- Relative field gradient : < 1.2 10-4 cm-1
Imge 4 & 5: Performances and production
- 83% polarisation in static mode
- 77-80% on neutron beam
- Production rate: 1.3 bar-litre / hour
- Final pressure: up to 4 bar