| 1250 | Mainly looking for a problem with DIB1pA, which is Side1pE. This channel was nonoperational for all of Run72/3, behaved as if it was open if I recall correctly. But it looks OK at tower check. Could it have been a problem at the SQUET?
Looking over the history, the channel showed continuity to other channels at 77 K. We tried two different DCRCs, each showed it behaved like open circuit. That rules out a lot. It could be a continuity break in the SQUET, in the signal coil branch or the other wire leading to the TES. |
| 1320 | Do electrical check on SQUET ZC-68 pA stuff. The four wires on the shunt resistor / input coil section all look fine, continuity and resistances all check out. |
| | So, the problem with DIB1pA (Side1pE) could instead be at detector level. Not as simple as a broken wirebond because we see continuity across the two pins. But maybe there's a break on the detector surface itself. In which case the room temperature resistance is conductance through the crystal rather than through the phonon channel rails. Which is a couple hundred Ohm at RT but becomes very high at base temp. That would explain all observations.
This problem first showed up after the Side2 etching. So the etching could have damaged it, or the rewirebonding may be related. This channel has complicated hopscotch wirebonding. |
| 1400 | Brought a scissor jack down from PAN443. This may be helpful for solo tower removal or install. |
| 1400 | Matt leaves lab |
| 1510 | Derek Sincavage body temperature = 97.9 °F |
| 1545 | Derek enters lab |
| 1600 | Remove 4K shield |
| 1620 | Remove 100mK heatsinks |
| 1625 | Remove inner pieces of 100mK shield |
| 1645 | Remove outer pieces of 100mK shield |
| 1650 | Untape thermometer plug from outside of 30mK can and unplug it. |
| 1655 | Derek leaves lab |