A Wide Temperature Range, Reliable, Compact Cryogenic Thermal Switch

Develop a reliable, compact cryogenic thermal switch to enable efficient cryogenic xenon collection in nuclear explosion monitoring systems. The thermal switch can be turned off during xenon removal, when the xenon cryotrap is heated up. This prevents the cryocooler cold head from overheating, and allows the system to return to its collection state quickly. Develop a thermosyphon that has an integrated actuator that has no moving parts to serve as the thermal switch. The actuator controls the thermal conductance of the thermosyphon. The thermosyphon uses a unique fluid mixture and an innovative configuration to enable it to operate over a wide temperature range (-50oC to -200oC). Commercial Application and Other Benefits: The thermal switch is very reliable because it has no moving parts. It also can operate over a very wide temperature range that none of the conventional cryogenic heat pipes can achieve. The technology can be widely used in many scientific and commercial cryogenic systems to significantly simplify the thermal integration between a cryocooler and a cooling target. Commercial applications include cryocooling systems for communication satellites; superconducting instruments, digital filters, and magnets; MRIs; and SQUIDs. Its national security applications include space-based surveillance, missile detection, and missile tracking systems. Scientific applications include cooling for space-based infrared observatories.