2021/07/22 (Thursday)
- Lab in-personnel: Pramod and Giulia
| Status | Run 74 in progress. First cooldown aftr IVC rebuild. |
|---|---|
| Tower thermometer is reading high, probably this is a thermometer problem and the actual temperature is much lower. High noise in some of the charge channels. | |
| Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/Source_mover_board+HV_diverter_board → DCRC50(3)/55(1). Kepco 40V supplye → HV BNC. No lead/poly shield. Currently both DCRCs are on. | |
| 1105 | Tower/MC/Coldplate = 129.1/35.5/ 192.4 mK, Still = 1.40 K / 0.08 mbar / 0 mW, G1/G2= 287.6/262.9 mbar, 1K Pot = 1.61 K / 20±1 mbar. MB = 67.8%. |
| 1110 | Fill LN2 cold trap bath. |
| 1152 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 1.54/1.04/1.77/5.1 e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 12/4/2.5/36 e-6 |
| These are more closer to yesterday. | |
| 1455 | Place Na-22 source 30 cm East of detector (center-to-center distance) on stand in lead castle. |
| 1503 | Start data but having trouble with triggering, abort series. |
| 1510 | Start 45 min series of 0V/-15V (bias applied after 70 sec), with Na-22 source at 0.30 m, with 1000 beginning randoms, trigger threshold 60/55/40/70 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| 1557 | Dial bias down to 0V and flash detector for 60 seconds |
| 1605 | Place Na-22 source 80 cm East of detector (center-to-center distance) on stand in lead castle. |
| 1614 | Fill LN2 cold trap bath, purge still disconnected. |
| 1650 | Start 45 min series of 0V/-15V (bias applied after 90 sec), with Na-22 source at 0.80 m, with 1000 beginning randoms, trigger threshold 55/50/45/60 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| 1738 | Dial bias down to 0V and flash detector for 60 seconds |
“rate” was calculated by counting events with E between 150 and 2000 keV in any channel, and normalizing to muons (qsum>7000). Then normalize to the Am-only case.