Infrared Imaging of Cryogen-Free NMR Superconducting Magnets with a variable temperature insert

Cryogen-free superconducting magnets are an attractive alternative to conventional liquid helium-cooled magnets with applications involving nuclear magnetic resonance (NMR), dynamic nuclear polarization (DNP), electron paramagnetic resonance (EPR) applications and Mossbauer effect between others, as they offer reduced operational costs since they don't require cryogen liquids such as liquid helium and/or nitrogen. However, cryogen-free magnets also pose new challenges in terms of thermal management and thermal stability, especially when they involve a variable temperature insert (VTI). In this study, we use infrared imaging to investigate the thermal behavior of a Cryogenic Ltd 9.4 T cryogen-free NMR magnet with incorporated VTI and how it may help to monitor the working of the system. We evaluate the effects of external disturbances, such as power outages on the magnet performance and safety and compare it with a wet 300 MHz Bruker magnet. Our results show the possibilities and advantages of infrared imaging as a monitor tool for cryogen-free NMR magnets.