By 2005 all repairs had been performed, and the camera was mounted at the prime focus station of the left primary mirror of LBT (see Figures 2-4).
All maintenance operations can be performed when the telescope is pointing toward the horizon and, possibly, with the swing arm in the 'out' position. By using a scissor lift we are able to carry out the pumping/ refilling/debugging operations.
The holding time of LN2, when LBC is mounted on the telescope, ranges between 40 and 50 hours, depending on the ambient temperature. The cooling time is about 15-18 hours while the working temperature of the array is 198±5K.
The vacuum level inside the cryostat is kept constant at 1.4*10-5 mbar by the carbon getter inside, and was found to be independent of both the elevation angle of the telescope and the rotator angle.
Figure 4. The blue channel of LBC.
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