| Status | Run 74 in progress. First cooldown after 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. Lead shield erected, 4 walls. Currently both DCRCs are on. |
| | Position of Am source: y = 0.0 mm |
| 1154 | Tower/MC/Coldplate = 98.2/35.2/191 mK, Still = 1.37 K / 0.070 mbar / 0 mW, G1/G2= 292/267 mbar, 1K Pot = 1.58 K / 10±1 mbar. MB = 35.7%. |
| 1200 | Fill LN2 cold trap bath. |
| 1430 | At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 1.9/1.2/1.3/8.1 8e-6. This is q3/q1/q4/q2
At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 10/2.8/1.9/33 e-6 |
| | Noise is very low today. |
| | The detector seems to be in a higher impact ionization state than it was a week ago. 12V is too high to get a reasonable looking curve, let's try 10V again. |
| 1447 | Start 45 min series of 10V/0V (bias applied after 60 sec), with 1000 beginning randoms, trigger threshold 40/30/40/60 on DCRC3qI/qO/DCRC1qI/qO, 5Hz in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length).
Use Sequencer script r74_takeandflash_dcrcbias.msl. This flashes for 30 seconds at end of series. |
