Detector

The mounting system for the pressure sensor was replaced with electrically isolating pieces to eliminate the noise induced by the actual sensors, so we can now monitor the pressure while operating the detector.

Although the FIES cold head is now close to -200 degrees again it is clear that we still do not really know what is going on, nor have any guarantee it will stay at such a low temperature. The main suspicion is that the vacuum of the dewar is poor and slowly degrading, but we do not have a properly working pressure sensor.

A vacuum sensor has been fitted with the electrically isolated clamp system. It was found that this caused light contamination. The dewar was opened and some baffling was added by PB which blocks the light.



Thomas Augusteijn 2010-11-19