| タイトル | Cryogen-Free Ultra-Low Temperature Cooling using a Continuous ADR |
| 著者（英） | Jirmanus, Munir; Shields, Bill; Shirron, Peter; DiPirro, Michael; Zhao, Zu-Yu |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2003-03-14 |
| 言語 | eng |
| 内容記述 | The development of a continuous adiabatic demagnetization refrigerator (CADR) has progressed to the point where we have demonstrated a 4-stage system that provides continuous cooling at 50 mK and below, while rejecting heat to a 4.2 K helium bath. Since temperature control and cycling of the ADR is fully automated, the system is simple to operate and stable. Temperature fluctuations of the cold tip are typically less than 10 microKelvin rms (at 100 mK). The ADR s cooling power of 2 1 microwatts at 100 mK is comparable to that of small dilution refrigerators, but because its efficiency is so much higher (50% of Carnot), the peak heat rejection rate is less than 10 mW. This is significant in allowing the ADR to be cooled by relatively low-power cryocoolers. In addition to commercial pulse-tube and Gifford McMahon (GM) coolers, this potentially includes small GM systems that run on 120 V power and do not need water cooling. The present focus is to design and fabricate a small dewar to house the CADR and a cryocooler, in anticipation of making a cryogen-free, low cost CADR commercially available. Performance of the prototype CADR and the complete system will be discussed. |
| NASA分類 | Engineering (General) |
| 権利 | No Copyright |
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