JanisULT successfully supplied a JDry-100-ASTRA cryogen free 3He-4He dilution refrigerator, which has an ability to work in a wide range of tilting angles -20 to +53 degrees from vertical, providing cooling power to a novel type of sensor for cosmic microwave background studies.
The instrument was installed in the cryogenic laboratory of the Physics Department of the University of Trento, in the framework of the MEMS collaboration between Istituto Nazionale di Fisica Nucleare (INFN) and the Instituto di Ricerca Sceintifica e Tecnologica of the Fondazione Bruno Kessler (FBK-irst). The telescope is used to test arrays of resonating bolometers (MKID) at ultra-low temperature to be used for the CMB polarization measurement on future space missions and ground based experiments.
The system employs a power-savvy and quiet pulse tube cryocooler with remote distribution valve. It takes only 40 hours to cool to the base temperature of 15 mK thanks to a common vacuum space and efficient mechanical heat-switch design.
The current system has a measured cooling power of 120 microwatts at 100 mK with a single mechanical vane pump, and can be upgraded to an automated gas handling system, JanisULT GHS2, equipped with a more powerful oil-free hermetic 6-stage Roots pump. This upgrade ensures full remote control of the cooling process, as well as higher cooling power.