Hydrogen Cooling Options for MgB2-based Superconducting Systems.

With the arrival of MgB2 for low-cost superconducting magnets, hydrogen cooling has become an interesting alternative to costly liquid helium. Hydrogen is generally regarded as the most efficient coolant in cryogenics and, in particular, is well suited for cooling superconducting magnets. Cooling methods need to take into account the specific quench propagation in the MgB2 magnet winding and facilitate a cryogenically reliable and safe cooling environment. The authors propose three different multi-coolant options for MRI scanners using helium or hydrogen within the same design framework. Furthermore, a design option for whole-body scanners which employs technology, components, fueling techniques and safety devices from the hydrogen automotive industry is presented, continuing the trend towards replacing helium with hydrogen as a safe and cost efficient coolant.