2020/09/06 (Sunday)
- Lab in-person: Matt
- Virtual partner: Michael
| 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). |
|---|---|
| 1740 | Matt Fritts body temperature = 98.4 |
| 1648 | MB = 55.2% |
| 1735 | Matt arrives at lab. |
| 1740 | Tower/MC/Coldplate = 50.2/31.4/196 mK, Still = 1.51 K / 0.095 mbar / 0 mW, G1/G2= 280/270 mbar, 1K Pot = 1.69 K / 45±2 mbar. |
| 1740 | Switch HV leads to -bias |
| 1745 | Fill LN2 cold trap bath. |
| 1750 | Matt leaves lab. |
| 2120 | Tower = 49.8 mK |
| 2120 | Turn on MC heater → 2 uW |
| 2148 | MB = 48.9% |
| 2155 | Tower seems to be settling to 54.4 mK with MC heater at 2 uW |
| 2205 | Matt Fritts body temperature 98.0 F |
| Planning to rerun -100V sequence done on Aug 27 at higher temperature, see if the counterbias growth rate looks different. | |
| 2215 | Start a 60 min series at HV = -100V, drifting 0.0298 V/s, prebias 15% for 2min, CDMS detector: Driver Gains = 1x, DCRC4/1 QET biases = (0,320,370,0)/(0,360,420,410)uA, Front-End Gains = (3/3/3)/(5/5/5) 1000 BOR & 5 Hz in-run randoms, trigger on DCRC1pD threshold = 8 Use sequence HVdrift_neg100V_pre15_2min_29p8mVps_multiloop10_60min.msl |
| The rampup took more than 10 minutes, implying that the DAQ is very laggy. Last time it took 4 minutes. | |
| 2215 | Tower = 54.5 mK |
| 2215 | Vtest = -4.0 mV shortly after drift begins. Drift appears to start at -102.8 V. 1.6% HV loss. |
| 2322 | Vtest = -9.0 mV, HV = -210.3 V, drift ends. 1.7% HV loss. Lag ratio = 1.1ish. good. |
| 2322 | Tower = 54.4 mK |
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| The gain does not fall any faster at this elevated temperature (if anything it falls slower). Gain is lower but this is expected because we didn't adjust the QET biases. |
| 0605 | Tower = 54.6 mK, MC Heater = 2 uW |
|---|---|
| 0605 | Turn off MC Heater |