DEIMOS CCD Dewar Characteristics

Background

The ESI CCD dewar is cooled by liquid nitrogen (LN) cryogen in order to maintain the detectors at their optimal operating temperateres of -120 C. This webpage describes adopted practices in achieving accepable dewar vacuum, timescale for cooling the dewar after a warm fill and for warming the dewar when cryogen is exhausted.

Acceptable Vacuum

TBD

Cooldown Curve

The following plot shows the behavior of the dewar temperature following a warm fill. The dewar can typically achieve the standard operating temperature within about 2.5 hours after the LN warm fill.

DEIMOS cooling plot Click to enlarge

Warmup Curve

TBD
Last modified: 03/12/2014 03:12
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