TITLE: 06/05 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: It's been a busy shift of troubleshooting. See alogs 78251, 78258, and 78259 for summaries of the first half of the day's events. Since then, we had trouble locking DRMI where buildups looked very unstable and there were several locklosses at different places in the DRMI acquisition steps. Eventually DRMI was able to lock (Jim reverted some sensor correction-like changes he put in Monday, but unsure if this had any effect) and we made it up to engaging ASC. Sheila had moved the DARM_OFFSET state to between the ENGAGE_ASC and SOFT_LOOPS states, but we found that increasing the DARM offset again caused the PRG to drop as we had been seeing in the morning. I wasn't fast enough to lower the DARM offset, so we lost lock. On the next attempt, we ran through both ENGAGE_ASC and SOFT_LOOPS before running DARM_OFFSET, but we still saw the drop in PRG as before. I was able to turn off the DARM offset in time, then Jenne started to step it up slowly to see where things became unstable. When she reaced the nominal value of 9e-5, things still looked okay and the OMC was able to lock, so we proceeded to DC readout and powered up to 25W. At this point, Robert went into the LVEA to take pictures through a HAM2 viewport, and sometime around then, we lost lock (unsure exactly if he was the cause). We've since relocked and continue to troubleshoot why we canot turn on the DARM offset reliably.
Handing off to Ibrahim as troubleshooting is ongoing.
LOG:
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
21:03 | SAF | HAZARD | LVEA | YES | LVEA is Laser HAZARD | Ongoing |
15:31 | FAC | Karen | Opt Lab | N | Technical cleaning | 15:56 |
16:24 | SQZ | Terry | Opt Lab | Local | SHG work | 18:55 |
19:48 | SQZ | Terry | Opt Lab | Local | SHG work | 23:47 |
20:09 | FAC | Mitchell | EY | N | Checking wind fence | 20:41 |
20:44 | VAC | Gerardo, Jordan | LVEA | - | Checking ion pump | 20:52 |
21:59 | CAL | Francisco | PCal Lab | N | Measurements | 23:59 |