2020/08/07 (Friday)
- Lab in-person: Zach
- Virtual partner: Matt
| Setup | Run 73. DIB 1/3/4 → Stripline 43/48/41 → pi-filters 1/2/3 → Cable 3/1/2 → nothing/nothing/accessory_interposer → HV_Conn 1/3/2 → HV 1/2 → DCRCX(4)/DCRC55(1)-master; DCRC33(2) → HV control. DCRCs on overnight. Lead/poly shield erected (4 lead walls, 2 poly walls). |
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| 1025 | Write a sequence for -20V data drifted at 24.9 mV/s HVdrift_neg20V_24p9mVps_multiloop10_nopre_60min.msl |
| 1026 | Start a 60 min series at HV = -20V, drifting 0.0249 V/s, no prebias, CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (0,320,370,0)/(0,360,420,420) uA, Front-End Gains = (3/3/3)/(5/5/5) 1000 BOR randoms, trigger on DCRC1pD threshold = 8 Use sequence HVdrift_neg20V_24p9mVps_multiloop10_nopre_60min.msl |
| 1026 | Tower = 51.4 mK |
| 1028 | Vtest = -1.2 mV shortly after drift begins. Drift appears to start at -19.3 V. |
| 1045 | Zach body temperature = 98.2 |
| 1047 | MB = 61.5% |
| 1105 | Zach arrives at lab |
| 1110 | Tower/MC/Coldplate = 51.2/35.3/193 mK, Still = 1.49 K / 0.17 mbar / 4 mW, G1/G2= 476/437 mbar, 1K Pot = 1.63 K / 24±2 mbar. |
| 1125 | Fill LN2 cold trap bath |
| Filling the LN2 caused the Tower temperature to rise a bit at the end of the data series, ending at around Tower = 53.0 mK | |
| 1132 | Vtest = -5.2 mV, HV = -108.7, drift ends. Lag ratio = 1.10. |
 |
| strange, increasing the drift rate had little effect the usual calculation suggests 25.5 mV/s, but let's try 26 mV/s |
| 1205 | Zach body temperature = 98.7 |
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| 1230 | Tower cooling slowly, now around 58.6 mK. Try turning off Still Heater. After a brief rise the tower cools faster, down to 55.4 after 30 minutes. |
| 1235 | Write new sequence for -20V drifted ate 26 mV/s HVdrift_neg20V_26p0mVps_multiloop10_nopre_60min.msl |
| 1305 | Tower cooling more slowly now, circulation pressures flattening out. Turn Still Heater back on, to 4 mW. |
| 1605 | Continued to mess around with Still Heater but frustratingly can't get the Tower very cool. Got it below 54 mK briefly but hard to keep it below 55 mK. |
| Well it's kinda warm, but let's take data anyway. | |
| 1633 | Start a 60 min series at HV = -20V, drifting 0.0260 V/s, no prebias, CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (0,320,370,0)/(0,360,420,420) uA, Front-End Gains = (3/3/3)/(5/5/5) 1000 BOR randoms, trigger on DCRC1pD threshold = 8 Use sequence HVdrift_neg20V_26p0mVps_multiloop10_nopre_60min.msl |
| 1635 | Tower = 55.3 mK |
| 1635 | Vtest = -1.2 mV shortly after drift begins. Drift appears to start at -19.4 V. |
| 1740 | Vtest = -5.6 mV, HV = -112.6, drift ends. Lag ratio = 1.12 |
| 1743 | 53.7 mK |
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| 2005 | Write a sequence to drift from -30V at 26.0 mV/s. HVdrift_neg30V_26p0mVps_multiloop10_nopre_60min.msl |
| 2015 | Start a 60 min series at HV = -30V, drifting 0.0260 V/s, no prebias, CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (0,320,370,0)/(0,360,420,420) uA, Front-End Gains = (3/3/3)/(5/5/5) 1000 BOR randoms, trigger on DCRC1pD threshold = 8 Use sequence HVdrift_neg30V_26p0mVps_multiloop10_nopre_60min.msl |
| 2016 | Tower = 53.1 mK |
| 2018 | Vtest = -1.8 mV shortly after drift begins. Drift appears to start at -29.2 V. |
| 2049 | MIDAS crash of some sort. Website lost connection (also both PuTTY sessions lost connection) then came back, sequencer continues but there is some error communicating with DCRCs, HV is staying at constant value. |
| 2055 | Stop sequence. HV is stuck at -77.4. This corresponds to /Charge/Bias = 9.7264. Turn off DAQ programs, then reset /Charge/Bias(V)[0] to 9.7264 on ODB. |
| Vtest = -3.8 mV when MIDAS crashed. | |
| 2100 | Turned the programs back on but they wouldn't work with all DCRCs enabled. Was able to start it with DCRC2 and DCRC1, which will allow for stepping down the bias and flashing. Write a temporary sequence to do this. |
| Sequence ran for 34 minutes and HV drifted from -29.2 to -77.4, so 23.6 mV/s. Lag ratio = 1.10, good. 46 dumps so the end of this will show falling Luke gain. (no, actually all dumps after the crash are empty.) |
 |
| Drift is too slow, estimating that it should be increased to 30.1 mV/s |
| 2048 | MB = 48.1% |
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| 2150 | Write new sequence to drift from -30V at 30.1 mV/s. HVdrift_neg30V_30p1mVps_multiloop10_nopre_60min.msl |
| 2243 | Start a 60 min series at HV = -30V, drifting 0.0301 V/s, no prebias, CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (0,320,370,0)/(0,360,420,420) uA, Front-End Gains = (3/3/3)/(5/5/5) 1000 BOR randoms, trigger on DCRC1pD threshold = 8 Use sequence HVdrift_neg30V_30p1mVps_multiloop10_nopre_60min.msl |
| 2244 | Tower = 53.9 mK |
| 2245 | Vtest = -1.7 mV shortly after drift begins. Drift appears to start at -29.2 V. |
| 2350 | Vtest = -6.7 mV, HV = -136.5, drift ends. Lag ratio = 1.12. |
| 2350 | Tower = 53.2 mK |
 |
| Drift is still a little slow, suggests increase to 33 mV/s |