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arXiv · 1405.7576

Sub-Kelvin refrigeration with dry-coolers on a rotating system

S. Oguri·H. Ishitsuka·J. Choi·M. Kawai·O. Tajima
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Abstract

We developed a cryogenic system on a rotating table that achieves sub-Kelvin conditions. The cryogenic system consists of a helium sorption cooler and a pulse tube cooler in a cryostat mounted on a rotating table. Two rotary-joint connectors for electricity and helium gas circulation enable the coolers to be operated and maintained with ease. We performed cool-down tests under a condition of continuous rotation at 20 rpm. We obtained a temperature of 0.23 K with a holding time of more than 24 hours, thus complying with catalog specifications. We monitored the system's performance for four weeks; two weeks with and without rotation. A few-percent difference in conditions was observed between these two states. Most applications can tolerate such a slight difference. The technology developed is useful for various scientific applications requiring sub-Kelvin conditions on rotating platforms.

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S. Oguri, H. Ishitsuka, J. Choi, M. Kawai, O. Tajima. 2014-07-18. Sub-Kelvin refrigeration with dry-coolers on a rotating system. https://doi.org/10.1063/1.4891618

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