aLIGO LHO Logbook

H1 General

edmond.merilh@LIGO.ORG - posted 12:40, Thursday 07 November 2019 - last comment - 16:36, Thursday 07 November 2019(53069)

Lockloss and Recovery 01:08UTC 18:09

18:09 Lockloss

Re-lock attempt -1

18:11 ALSY needed aligning

18:23 FIND_IR starting

no diff IR- offset in TRY_QPD_B_SUM

18:35 Lockloss - trying to play catch-up with diff slider

18:39 Re-lock attempt - 2

DRMI was very misaligned; Guardian to PRMI - no lock; 20 minute timeout as per threshold protocol

19:10 Initial Alignment

19:25 IA complete

19:27 Re-Lock attempt - 3

19:52 Lockloss @ LOWNOISE_ASC

19:53 Re-Lock attempt -4

after 2 minute I realized there was the offset in te Y QPD BSUM again (started FIND-IR @ 19:56)

20:06 lockloss

20:07 Re-Lock attempt- 5

20:37 NLN

Comments related to this report

thomas.shaffer@LIGO.ORG - 15:17, Thursday 07 November 2019 (53074)Lockloss

Link

Lock loss 1257185391

A very fast lock loss. I didn't see anything in the ASC signals (1st attachment), then I noticed that the squeezer lost lock just before the rest of the IFO (2nd attachment). I'm not sure how to tell if the squeezer losing lock was a cause or effect though.

Anther oddity is the slight jitter in H1:SUS-ETMX_L3_MASTER_OUT channel just before the lock loss. It seems to have large amounts of drive almost .4 seconds before. Out of time time to track down from where.

Images attached to this comment

thomas.shaffer@LIGO.ORG - 16:36, Thursday 07 November 2019 (53077)

Link

One more, I looked at H1:SQZ-LO_SERVO_CTRL_OUT_DQ and it loses it before the main IFO.

Images attached to this comment