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SCUBA-2 is a world leading wide field submillimeter camera on the JCMT, producing a wide range of science results, including a unique series of large survey programs. The SCUBA-2 instrument and TES detector arrays have been in constant operation for over a decade at JCMT. The arrays are Transition Edge Sensors fabricated on 3” silicon wafers and read out by a Superconducting Quantum Interference Device (SQUID) multiplexer. Each wafer has an array of 32x40 TES bolometers with the associated SQUID readout. The camera has in total eight TES arrays, four at each wavelength band. With each array having 1,280 bolometers there are in total 5,120 bolometers per wavelength. The instrument is cooled by three pulse tube coolers and a dilution refrigerator. The dilution fridge, with its own pulse tube cooler, has a base temperature of about 50mK. The cryostat itself is very large so that it can accommodate the three large mirrors, located in the 1K optics box, for the field of view of 43 sqarcmins. The other two pulse tube coolers keep the mirrors at temperatures below 10K to minimize the thermal background on the arrays. Mounted within the 1K box are the two focal plane units that contain the cold electronics and the 450μm and 850μm arrays, which are cooled to below 100mK. The still and mixing chamber of the liquid cryogen-free dilution refrigerator cool the 1K box and arrays respectively. The cold shutter is the only moving mechanism within the instrument and is critical for taking dark frames. The shutter is mounted on the outside of the 1K box and provides a uniform background (at roughly 1K) to the arrays. In this paper we review the performance of (a) the NIST fabricated TES wafters and 2D Time Domain SQUID MUX over the past ten years and numerous thermal cycles, (b) the cryogens, which consists of the original liquid cryogen-free dilution fridge and three Cryomech pulse tubes and (c) the cryostat, including the cold shutter.
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