2013/03/20

1000	Filled LN2 cold trap.
1030	Fed Cricket 4 pellets.

Overnight Temp and Pressure

1133	Mixing chamber temp: 60.8 mK. G1 ~ 85.3 mbar, G2 ~ 80.2 mbar. P1 ~ 0.085 mbar. 1 K pot temperature: 1.728 K.
1411	Begin flashing detector for 20 minutes, then cool down for 1 hour. Take one 30 min series at + 4 V for Dib 2. Trigger for Qi channel.
1508	Hook up leak checker to vent in back of IGH. Turn on. Currently G1:86.1mbar, G2:81.4mbar, P1:0.085mbar, P2:50.0mbar, 1K Pot: 1.731K.
1512	Switch to exhaust. Pause pumping on 1K Pot by closing 4A, then open 5A and 2A to pump on vent, open V7. P2 at 0.016mbar.
1514	Open vent speedivalve to pump on line to leak checker. P2 maxed at ~25mbar and stopped at 0.02mbar. Once line is evacuated close V2A and 5A, open 4A to continue pumping on 1K pot and switch back to recovery.
1535	Calibrate leak checker take background rate (Settled to 1.1E-10 mbarl/s by 15:45).
1548	Open leak checker to line. Leak rate eventually settled to 3.4E-8mbarl/s by 16:20. At this point we decided to warm up the cold trap before performing leak check.
1628	Close vent speedivalve and isolate leak checker. At this point G1:87.8mbar, G2:80.1mbar, P1:0.085mbar, P2:50.0mbar, 1K pot: 1.732K.
1632	Switch to exhaust, close 4A (isolate 1K pot), open V5A, 2A, 11A and remove cold trap 1 from LN2.
1635	Open V4A to pump on both 1K pot and cold trap 1.
1717	Open leak checker to vent (vent speedivalve is closed). Leak rate at 4.6E-9mbarl/s.
1729	After waiting for cold trap 1 to reach room temp, leak rate has reached 4.1E-9mbarl/s. Close V5A and V2A, and switch back to recovery.
1731	Open vent speedivalve, allowing leak checker to pump on cold trap 1. Leak rate climbed to 1E-1mbarl/s. Closed vent speedivalve. Panic sets in. Although we had been pumping on it with the He4 pump, there was enough stuff present in the “clean” cold trap 1 to overwhelm the leak checker. Perhaps this is a sign of a leak, or perhaps the cold trap is haunted.

Leak Checker Issues
After we isolate leak checker, we found that there was still and internal background leak rate of 4.6E-8mbarl/s. We decided to temporarily abandon the idea of performing a leak check on the cold trap in order to allow the leak checker to recuperate. After deciphering a very vague manual we were able to begin regeneration at 19:15. After regeneration and calibration the internal background leak rate was at 1.4E-8mbarl/s (measured at 20:28). Second round of regeneration started 20:30.

Leak Checker Issues

After we isolate leak checker, we found that there was still and internal background leak rate of 4.6E-8mbarl/s. We decided to temporarily abandon the idea of performing a leak check on the cold trap in order to allow the leak checker to recuperate. After deciphering a very vague manual we were able to begin regeneration at 19:15. After regeneration and calibration the internal background leak rate was at 1.4E-8mbarl/s (measured at 20:28). Second round of regeneration started 20:30.

1741	Switch to exhaust and open V2A and 5A to allow He4 pump to pump on cold trap 1. Open vent speedivalve.
1821	Noticed sharp increase in G1 and G2 and a fridge temp decrease, suggesting that a blockage has occured. With a blockage we will not be able to perform the test on cold trap 2 that we had planned. We will now pump the mixture behind the cold traps and prepare to clean He cold trap and cold trap 2. Cold trap 1 is already clean.
1834	Closed gate and condenser valves. Close V13B and open 5.
1935	G1 currently at 2.2 mbar. Open 12A, no change in G1.
1937	Closed 12A and 12B (V1 still open). G1 drops to 0.3mbar. Close V1 and open 12B. G1 climbs to 2.0mbar.
2022	Filled LN2 cold traps full.
2037	G1 fluctuating around 1.4mbar.
2232	Fed Cricket 4 pellets.
2323	Finished 3 rounds of cold trap cleaning.

DCRC 32, Dib2, +4 V data; 23 ADC bin ; 30 minutes

Fig. 1: Qi and Qo, with threshold cut (Qi, Qo > 0.25 [1000 a.u.])	Fig. 2: Qpart, no cuts.

Fig. 3: Chi2 vs. Charge (top figure, no cuts; bottom figure - threshold, qpart, and chi2 cuts)	Fig. 4: Qsum (top figure- threshold cut; bottom figure - threshold, qpart, and chi2 cuts).