Heliox (cryogenic equipment)
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Heliox is a cryogenically cooled system produced by Oxford Instruments.
Presently available in 2 varieties, the VL and TL, vertically-loaded and top-loaded respectively. They are both pumped He3 cryostats, the TL capable of magnetic fields of up to 14 T, and the VL capable of achieving magnetic fields of up to 2 T. The base temperature for both systems is ~250 mK. Whilst the basis of operation of system is pumping of liquid Helium 3 below 2.2 K, this low temperature is achieved by first cooling the system to 2.2 K by pumping of Helium 4. A constant supply of liquid He4 is necessary, constituting a typical overhead of ~£1 / litre, whilst He3 is efficiently conserved as it is valued at ~£300 / litre!.