Pumping of continuosly or discontinously 3He operated cryostats, also
on 3He and 4He mixed cryostats
- In these cryostats the very
expensive helium isotope 3He,
respectively mixtures consisting of
3He and 4He are pumped and this
is generally done continously in
cycles running over weeks.
The gas must neither be lost nor
contaminated. For this reason
exhaust lines are frequently
operated at low pressures of
100 mbar (absol