aLIGO LHO Logbook

LHO General

corey.gray@LIGO.ORG - posted 07:42, Wednesday 06 November 2024 - last comment - 10:26, Wednesday 06 November 2024(81092)

Wed DAY Ops Transition

TITLE: 11/06 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Aligning
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 6mph Gusts, 4mph 3min avg
    Primary useism: 0.16 μm/s
    Secondary useism: 0.18 μm/s
QUICK SUMMARY:

H1 had a 6.5hr lock overnight (after waking up Ibrahim), and just went down about 30min ago due to a M5.9 EQ in the Solomon Islands (switching Observatory Mode to EARTHQUAKE). ISC LOCK is currently running an automatic alignment.

Microseism continues it's trend downward. Winds are negligible.

Comments related to this report

camilla.compton@LIGO.ORG - 08:36, Wednesday 06 November 2024 (81094)PSL

Link

As noted by Jason and Ryan S yesterday 81073, the power out of the PSL is again not stable. Fluctuating from 1.2 to 2.7W. There's not a known solution for this so we will sit with ISC_LOCK in IDLE until this stabilizes.

The IMC is saying it's locked but the power out if wildly fluctuating from 2W to 50W so we took it to OFFLINE. Plot.

Images attached to this comment

camilla.compton@LIGO.ORG - 09:17, Wednesday 06 November 2024 (81098)

Link

At 17:10UTC this NPRO behavior calmed down and Jason locked the ISS and FSS. I took LASER_PWR to POWER_2W then IMC_LOCK to LOCKED then started the main locking process.

camilla.compton@LIGO.ORG - 10:26, Wednesday 06 November 2024 (81100)PSL

Link

Attached plot showing comparison to Jason/Oli's plot from 81099. You can see:

NPRO power before the PMC (top right LASER_AMP2_PWR) is stable.
Even after FSS and ISS is taken DOWN, the REFL and TRANS power from the OMC are not stable.
We are unsure if the IMC IM4 TRANS power is physical or if there's some strange calibration happening here to output 50W out when the IMC. This plot shows that ASC_A IMC_MC2_TRANS and Keita's new AS_AIR channel do see power fluctuations at this time.

Images attached to this comment