Helium Loop Heat Pipe for Large Area Cryocooling

To take full advantage of the space environment, Far Infrared (FIR)/Submillimeter (SMM) interferometers require cold mirrors (4 K) and detectors (0.1 K or colder). The collecting mirrors for the proposed FIR/SMM missions are large. The most difficult challenge will be the 4K cryocooling of the entire telescope structure. Given long duration of the missions, stored cryogens do not present an attractive option. Hence, an active cryocooling system capable of removing 10-100mW at 4K is absolutely essential for the mission success. The cryocooling system must provide continuous operation and not cause significant vibrations of the optical components. In addition, the cooling power will have to be distributed over large mirror surfaces.To meet the challenging cryocooling requirements of the FIR/SMM missions mentioned above, TTH Research proposes the development of an advanced capillary pumped cryo-cooling transport system operating at 4K. Despite the fact that the CPL/LHP technology has reached a high level of maturity, the proposed research effort will demand a host of technology innovations that do not exist at the present time. Among them are the use of Helium as the working fluid in CPLs/LHPs and cooling over large areas at cryogenic temperatures.