Goldman thermometer is reading wrong….
last run: Goldman thermometer (wired through striplines) and Tower thermometer (using fridge thermometer wires) - Goldman read correctly, Tower was wrong
between runs: checked for problems with fridge thermometer wiring. No leakage between wires seen at room temperature (> 1 GΩ)
this run: assumed Tower thermometer itself was the problem, so using Goldman thermometer with fridge wires
conclusion: something wrong with fridge thermometer wires.
Goldman reading ~ 80 mK but this is definitely not correct, probably ≤40 mK. Could be explained by a ~50 kΩ leak between wires… ?
Unclear how to fix this. Likely any new problem with these wires is somewhere near the bottom where there's activity. Maybe replace lower section of the wiring.