Use of good copper for the optimization of the cooling down procedure of large masses

Year: 2004

Authors: Risegari L., Barucci M., Bucci C., Fafone V., Gorla P., Giuliani A., Olivieri E., Pasca E., Pirro S., Quintieri L., Rocchi A., Ventura G.

Autors Affiliation: Department of Mechanics, University of Florence, Firenze I-50125, Italy; INFM, Unity of Florence, Firenze I-50125, Italy; Department of Physics, University of Florence, Firenze I-50125, Italy; INFN, Laboratori Nazionali del Gran Sasso, Assegi (AQ) I-67010, Italy; Nucl./High Energy Physics Laboratory, University of Zaragoza, Zaragoza 50009, Spain; Dipartimento di Scienze Chimiche, Università dell\’Insubria, Via Valleggio 11, Como I-22100, Italy; INFN, Sezione di Milano, Milano, Italy; INFN, Laboratori Nazionali di Frascati, Frascati (Roma) I-00044, Italy; Department of Physics, University of Rome-Tor Vergata, INFN, Sezione di Roma 2, Roma I-00133, Italy

Abstract: Purpose of this experiment was to select the best material for the construction of thermal links aiming at cooling down sensitive masses of the order of 100-1000 kg for the detection of rare decays and gravitational waves. We report on the technique used to measure the thermal conductivity at very low temperatures (down to 30 mK) of three different types of copper, before and after a thermal treatment of the samples. The most conductive copper was used for the thermal link of the CUORICINO experiment, where a mass of about 60 kg needs to be cooled down to a few mK. The cool down time was reduced by at least one order of magnitude with respect to previous similar experiments. An important contribution to this successful result came also from an improved procedure for controlling the residual heating provided by the conversion from ortho- to para-hydrogen in copper.

Journal/Review: CRYOGENICS (GUILDF.)

Volume: 44 (3)      Pages from: 167  to: 170

KeyWords: Antenna arrays; Copper; Electric conductance; Gravity waves; High temperature effects; Low temperature effects; Mixing; Phase equilibria; Refrigerators; Stainless steel; Steady flow; Thermal conductivity; Thermometers; Vacuum, Residual heating; Thermal links, Cooling
DOI: 10.1016/j.cryogenics.2003.09.004