UMN CDMS Wiki archive
start › cdms › k100 › run_diary › 20151009

2015/10/09 (Friday)

Previous Day

Overnight status: taking background data.
0900 Tower/MC(H35)/MC sensor/Cold Plate = 31.1/25.6/40.6/159 mK, Still = 1.36 K / 0.11 mbar, G1/G2 = 205/185 mbar, 1K Pot = 1.72 K / 22 mbar, Main bath = 49.3%
Readings above taken just before a series (final one probably) started
0905 Fill LN2 cold trap full.
1010 250Hz sinusoidal noise no longer appears on phonon channels. May have gone away during the night.
1025 Putting Ba source on back of fridge inside topmost part of shield.
1029 Set phonon thresholds to values from 2015/10/02. Move DCRCs closer together back to their original positions. Start 5 cycles of 15min series of Ba data at -/+4V, FG=5/2/5, OG=3, with 1000 initial randoms, 2000 events/file, 30s flashing and 30min cooldown in between.
1503 Put Ba source back in safe.
1521 Commence LHe transfer (38%)
1642 Cease LHe transfer (93.1%)
1653 Start background data 50 cycles of 15min series at -/+2V, FG=5/2/5, OG=3, with 1000 initial randoms, 2000 events/file, 30s flashing and 30min cooldown in between.
1655 Move DCRCs farther apart while the data's being taken. This caused DIB1 pB to rail, so stop data and relock channel.
1709 Cannot bring channel DIB1 pB back. It began doing that jagged noise thing, where it looks like it's been driven normal . Try viewing the modulation curve, but cannot get test signal to show up on that channel. Can't get one to show up on pA either, so maybe the board's just a lost cause. Power cycle.
1735 After repowering DCRC55, channel B is back, but it's got huge spikes at approximately 83Hz.
1740 Fill LN2 cold trap full.
1745 The spikes on DIB1 pB change into a full fledged test signal triangle wave of 83Hz. It won't go away. Unpower board.
1750 Place Cf source inside shield near detector for overnight activation.
1800 Repower DCRC55.

Next Day