Reports until 18:55, Tuesday 17 October 2023
H1 General (Lockloss)
oli.patane@LIGO.ORG - posted 18:55, Tuesday 17 October 2023 - last comment - 11:03, Wednesday 18 October 2023(73539)
Lockloss

Lockloss @ 10/18 01:53UTC

Comments related to this report
oli.patane@LIGO.ORG - 20:17, Tuesday 17 October 2023 (73541)

DARM_IN1(attachment1) saw some sort of glitch(left data tip) ~170ms before DARM registered the lockloss starting(right data tip).

ETMX L2 and L3 also saw this glitch(attachment2). Seems like the glitch hit DARM_IN1, then ETMX L3, then ETMX L2?

I noticed something similar with the 10/15 08:53UTC LL(attachment3), but in that case it looked like the movement was first seen in ETMX L3, then DARM_IN1 and ETMX L2. In that instance the glitch also happened a full 0.5s before the lockloss.

Images attached to this comment
oli.patane@LIGO.ORG - 20:26, Tuesday 17 October 2023 (73542)

03:25 Back Observing

thomas.shaffer@LIGO.ORG - 11:03, Wednesday 18 October 2023 (73552)Lockloss

Very interesting find Oli! I've attached some more plots to hopefully help us narrow down where this is coming from. The L2 ETMX fastimon and noisemon channels see this same glitch, but the L2 OSEM sensor inputs on all of the quads don't. This makes me think that it could possible be coming from the OMC DCPD signals, the error signals forLSC-DARM. Tough to say based on data rates, but the second attachement also maybe shows the DCPD signal moving first, but take that with a grain of salt.

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