Achieving the stringent instrument performance for the most demanding astrophysics missions requires the capability to cool the detectors to cryogenics temperatures as low as 50 mK. The dilution refrigerator is an attractive candidate due in part to its continuous operation. This cryo-refrigerator relies on helium circulation and the capability for low pressure pumping to reach extremely low temperatures. The required long-life duration and mass constraints of space instruments makes the standard ground base technology for fluid circulation difficult to implement.
A proof of concept for a generic use helium circulator is presented, with a case study on the integration into a space dilution refrigerator (CCDR type). This circulator will be based on the cryosorption of activated carbon, a mechanism that generates pressure oscillations from temperature variations. We propose an innovative coupling that will optimize the energy required to cycle the temperature of the activated carbon. Another key component of the device is a one-way check valve operating at low temperature, in order to convert the pressure oscillations into unidirectional flow. The approach of our work combines thermodynamic modeling, mechanical design, and experimental validation. An overview of the concept and the preliminary validation will be presented.

Keywords
Cryogenics|Circulators|Helium