• Measured and Calculated Performance of a High Frequency, 4 K Stage, He-3 Regenerator 

      Garaway, I.; Lewis, M. A.; Bradley, P. E.; Radebaugh, R. (Georgia Institute of TechnologyICC Press, 2008-05)
      Efficiencies of small 4 K cryocoolers are less than 1% of Carnot, whereas 80 K cryocoolers achieve efficiencies of up to almost 20% of Carnot. The primary loss mechanisms in low temperature regenerative cryocoolers are ...