Monday: after 5K pumpout, temperature spikes returned. But IbIs behavior looked closer to normal, suggesting no problem with helium buildup on detector - and 0V data looked good, Am lines clearly resolved
Tuesday: temperature instabilities worse, and strangely the phonon channels looked stuck in normal state, couldn't get them into transition
Wednesday: IbIs suggested helium buildup had returned. High biases needed on inner channels; two outer channels were stuck in superconducting.
Tightened a few valves and tried another 5K pumpout. This time choosing not to pump on IVC continuously, since not pumping on it worked fine for first months of run
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