corey.gray@LIGO.ORG - posted 07:41, Friday 18 July 2025 - last comment - 10:40, Friday 18 July 2025(85841)
Fri Ops Day Transition
TITLE: 07/18 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 5mph Gusts, 1mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.12 μm/s
QUICK SUMMARY:
H1's been locked for 1.25hrs w/ 4 locklosses over night each with decent recovery times. Microseism is trending down over last 24hrs; forecast is for high winds (redflag warning) in the afternoon.
The lockloss that occurred at 2025-07-18 08:00 UTC (not tagged as a glitch) was preceded by what appears to be a large kick in the yaw ASC. First attachment shows the CSOFT Y and CHARD Y signals a few seconds before the locklosses. This is also apparent in the test mass L2 signals in the second attachment.
Of the 4 locklosses overnight, we had (1) ETMx Glitch lockloss.
The other two locklosses last night seem by eye to have the same behavior (2025-07-18 12:07:24 UTC and 2025-07-18 04:20:15 UTC). Within ~100 ms of the lockloss time, there is something glitchy in the darm error signal where the error signal drops sharply. It looks like the glitchy behavior starts in DARM IN1 slightly before ETMX L3 starts behaving weirdly, but that's hard to tell since I'm just looking at ndscopes.