2019/05/25 (Satuday)
| Status: | LHe transfer yesterday. Weird issues writing to chocula continue. |
|---|---|
| 0844 | MC(Cernox) = 4.7 K, Sorb = 8.4 K, turbo on IVC = 0.86 nbar, G1 (fridge) = 559 mbar, DIB4 pD SQUID = 311 Ω |
| 0849 | Quick electrical check looks good. |
| 0852 | Plug DIB3 into DCRC3 and power it up. Start DCRC programs. |
| 0855 | Try to use DCRC Control tools to zap DCRC3 SQUIDs, but keep getting 'problem in tools timeout' error. I know that this just creates a sequence called 'testzap.msl'. Looking at the existing version of it, I see it is the correct sequence to zap just DCRC3 SQUIDs since that's the last time we used it. Just run 'testzap.msl' sequence through MIDAS sequencer so we can get on with things. |
| 0900 | Just looking at PSDs on the pulse viewer, it looks like DIB3 PD (SQUID only) has very low, flat noise at around 2.48e-7 @ 1kHz (in some units? Not sure how the SQUID tuning GUI PSD is normalized). DIB3 PB has a flat spectrum at 3.45e-6 with R/L roll off as expected for Johnson noise. |
| 0902 | Let's try a baby IbIs with DCRC3 pB. Looks nice and linear with slope of -16.9 mV/uA As described on the Run 70 summary, this implies a wirebond (pair) resistance of 5.0 mΩ |
| Ib (uA) | Vo (V) |
|---|---|
| -10 | -0.1753 |
| -5 | -0.2613 |
| 0 | -0.3445 |
| 5 | -0.4284 |
| 10 | -0.5129 |
| 0906 | Start 100s series with 20 Hz in run randoms and 1000 BOR randoms, DCRC3 PB/PD QET bias = 0, and phonon trace length = 52.4288 ms |
|---|---|
| 0908 | MC(Cernox) = 4.7 K, Sorb/1K Pot = 8.4/6.6 K, G1 (fridge) = 559 mbar |
| 0909 | Pump out lines leading to 1K Pot with scroll pump |
| 0911 | Switch over to 4He pump. Change pump exhaust to recovery and open valve to recovery lines. |
| 0916 | Check pressure in 1K Pot by closing V4A and opening 1K Pot speedivalve: the mechanical gauge goes up about 0.3 bar This brought the 1K Pot temp down to 3.5 K |
| 0918 | Pump out 1K Pot in steps, alternating between V4a and the 1K Pot speedivalve. After 5 iterations get pot down to < 0.1 bar. Then leave 4He pump pumping on pot continuously. |
| 0921 | 1K Pot = 3.2 K / 3.2 mbar. MC (Cernox) = 4.69 K and falling slowly, G1 = 533 mbar and falling slowly. |
| 0925 | 1K Pot = 3.2 K / 3.2 mbar, steady. |
| 0926 | Open 1K Pot needle valve → 10°. 1K Pot → 2.7 K / 8.0 mbar Needle valve was closed about 5° past the 0 marked on the brass knob. It was a little sticky to open at first, but not as bad as yesterday. |
| 0927 | MC = 4.6 K and falling, G1 = 484 mbar and falling. |
| 0930 | Open 1K Pot needle valve → 20°. 1K Pot → 2.4 K / 19.0 mbar |
| 0932 | Open 1K Pot needle valve → 30°. 1K Pot → 2.0 K / 38.0 mbar |
| 0935 | MC = 3.1 K and falling G1 = 375 mbar and falling. |
| 0938 | Open 1K Pot needle valve → 40°. 1K Pot pressure (P2) spikes to 260 mbar, but then starts falling slowly. |
| 0940 | 1K Pot = 1.8 K (flat) / 190 mbar (falling), MC = 2.8 K and falling G1 = 248 mbar and falling. |
| 0945 | Do another baby IbIs. Linear with a slope of -17.1 mV/uA giving wirebond (pair) resistance of 4.8 mΩ |
| Ib (uA) | Vo (V) |
|---|---|
| -10 | -0.0959 |
| -5 | -0.1821 |
| 0 | -0.2679 |
| 5 | -0.3525 |
| 10 | -0.4378 |
| 0947 | 1K Pot = 1.7 K / 55 mbar (falling), MC = 2.5 K and falling G1 = 135 mbar and falling. |
|---|---|
| 0949 | Just looking at PSDs on the pulse viewer, DIB3 PD (SQUID only) has very low, flat noise at around 2.36e-7 @ 1kHz. DIB3 PB has a flat spectrum at 2.40e-6 with R/L roll off. |
| 0955 | The chocula issues are messing with the fridge temp plots on the K100 status website. Temporarily move this code from chocula to my personal directory and make a link to it from the chocula location. Ughh,that doesn't help because the logs are all supposed to be written to chocula. Not sure if the fridge logs are being written. I notified IT about this yesterday, but haven't heard back. Looks like the data I took got copied to chocula fine though, so that's good. |
| 1000 | 1K Pot = 1.6 K / 16 mbar (flattening out), MC = 2.1 K, G1 = 63 mbar. Everything is starting to flatten out. |
| 1003 | Spontaneous jump in 1K Pot pressure → 1.75 K / 300 mbar and oscillating strongly. |
| 1006 | Close 1K Pot needle valve → 35°. 1K Pot → 1.70 K / 150 mbar and oscillating |
| 1008 | MC = 2.1 K, G1 = 62 mbar. Both quite flat. |
| 1013 | Close 1K Pot needle valve → 30°. 1K Pot → 1.72 K / 85 mbar. That seems a little more stable. |
| 1016 | Fill LN2 cold trap bath. |
| 1017 | Close V3 and V9, leaving 61 mbar in the dump. Start circulation through Trap 1. V6 → 12.5%. No immediate changes. |
| 1020 | V6 → 12.8%. No changes, MC (Cernox) = 2.0 K, G1 = 58 mbar |
| 1024 | V6 → 13.0%. MC (Cernox) = 2.0 K, G1 = 60 mbar, 1K Pot = 1.72 K / 75 mbar |
| 1026 | V6 → 13.2%. Condenser peaks at 82 mbar. MC (Cernox) falls to 1.97 K. 1K Pot steady at 1.72 K / 70 mbar |
| 1029 | V6 → 13.4%. Condenser peaks at 138 mbar. MC (Cernox) falls to 1.56 K. 1K Pot steady at 1.72 K / 70 mbar |
| 1030 | Let's leave 10uA bias going down DCRC3pB and just watch the DC level. I think this should go down when the wirebonds go SC. DCRC3pB = -0.4375 V |
| 1034 | V6 → 13.6%. Condenser peaks at 130 mbar. MC (Cernox) falls to 1.47 K. 1K Pot steady at 1.72 K / 70 mbar. P1 comes within range |
| 1038 | V6 → 13.8%. Condenser peaks at 125 mbar. Still → 13 mbar. Tower → 1.28 K. DCRC3pB = -0.4373 V Switched over to tower thermometer |
| 1042 | V6 → 14.0%. Condenser peaks at 120 mbar. Still → 4 mbar. Tower → 1.20 K. DCRC3pB = -0.4379 V |
| 1044 | V6 → 14.4%. Condenser → 132 mbar. Still → 2.6 mbar. Tower → 0.99 K. DCRC3pB = -0.4381 V |
| 1050 | V6 → 15.0%. Condenser → 136 mbar. Still → 1.3 mbar. Tower → 874 mK. DCRC3pB = -0.4383 V |
| 1052 | V6 → 16.0%. Condenser → 136 mbar. Still → 0.60 mbar. Tower → 717 mK. DCRC3pB = -0.4381 V |
| 1052 | V6 → 100%. Condenser → 137 mbar. Still → 0.20 mbar. Tower → 591 mK. DCRC3pB drops to -0.4428 V, then starts rising again. 1K Pot = 1.72 K / 80 mbar |
| 1101 | Omni-logger saves it's log to chocula. Today's log looks screwy, it's missing the header and hasn't been updated in a while. Probably due to chocula write issues. Stop OMNI-logger, delete today's temp log file and restart Omni-logger. Now the log file looks correct and is updating. |
| 1105 | Tower = 400 mK, Still = 0.170 mbar, Condenser = 130 mbar, 1K Pot = 1.72 K / 75 mbar. DCRC3pB = -0.4381 V |
| 1110 | Fix a badly formatted line in yesterday's log too. Now the K100_Plotter script should work and keep the website updated. |
| 1115 | Tower = 229 mK, Still = 0.140 mbar, Condenser = 108 mbar, 1K Pot = 1.71 K / 70 mbar. DCRC3pB = -0.4378 V |
| 1124 | Tower = 88.6 mK, Still = 0.110 mbar, Condenser = 90 mbar, 1K Pot = 1.72 K / 80 mbar. DCRC3pB = -0.4379 V |
| 1128 | Open V14 to let the remaining mix out of the dump and into circulation. P1(Still) rises off scale, falls again after a minute. Condenser peaks at 115 mbar. Tower → 100 mK and rising. 1K Pot peaks at 1.72 K / 100 mbar then settles. |
| 1133 | Tower peaks at = 128 mK, Still = 6.0 mbar, Condenser = 79 mbar, 1K Pot = 1.72 K / 70 mbar. DCRC3pB = -0.4379 V |
| 1140 | MB = 54.4% Depending on the boiloff rate, this could be down to 20% by as early as 8AM tomorrow. Let's do a little fill now to get on a schedule of non-ish transfers. |
| 1141 | Tower = 94.3 mK, Still = 2.20 mbar, Condenser = 78 mbar, 1K Pot = 1.72 K / 80 mbar. DCRC3pB = -0.4378 V |
| 1150 | Modify the webcamAutomater.py script to accept device number as a parameter. Plug recovery webcam into jiajin. Run python /home/mast/cdms/webcam webcamAutomater.py -device /dev/video1 -delay_min 0.033 -total_time_hr 3 -save_images to save images every ~2 sec |
| 1152 | P1 = 0.85 mbar, close V14. |
| 1155 | Commence LHe transfer, MB = 53.4% 1K Pot pressure runs off scale, then settles back down and starts to oscillate around 150 mbar |
| 1200 | Tower = 83.4 mK, Still = 0.110 mbar, Condenser = 87 mbar, 1K Pot = 1.73 K / 160 mbar (oscillating). DCRC3pB = -0.4387 V |
| 1210 | Tower = 81.9 mK, Still = 0.110 mbar, Condenser = 84 mbar, 1K Pot = 1.71 K / 80 mbar . DCRC3pB = -0.4375 V |
| 1211 | Turn on heater on LHe dewar to 4PSIg |
| 1213 | Temperature log has stopped updating again. :/ Ohh, I see now that chocula is full. That's a problem. |
| 1235 | Cease LHe transfer, MB = 91.3% |
| 1237 | Tower/MC/Coldplate = 81.7/33.5/200 mK, Still = 1.0±0.1 K / 0.110 mbar, G1/G2 = 83/92 mbar, 1K Pot = 1.68 K / 45 mbar. MB = 91.3%. DCRC3pB = -0.4369 V Still is usually at ~1.7 K |
| 1251 | Fill LN2 cold trap. |
| 1300 | Things look mostly stable, though P2 falling slowly, hopefully it settles out. The temperature logging isn't working, but we should still be able to VNC to vuk1 to check on things. |
| 1430 | Tower = 80.7 mK, 1K Pot = 1.7 K / 36 mbar |
| 1630 | Tower = 79.9 mK, 1K Pot = 1.66 K / 32 mbar |
| 2150 | Tower = 78.2 mK, 1K Pot = 1.65 K / 30 mbar |