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We tried stopping the freezing on the outside with with plastic bags and heaters.
We had kapton windows fail and tried many different iterations and now we have a fairly confident mechanical solution.
We tried different sized pedal stools and wrapping of cables and shields of the cold finger.
We even changed out our crystats. We have a flow cyrostat now when we initially tried a pumping. We could not get spatial overlap with the closed loop.
Now we are at ~9 on the copper plate and 4-5K on the cold finger.
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