gabriele.vajente@LIGO.ORG - posted 12:59, Thursday 21 March 2024 - last comment - 09:22, Friday 22 March 2024(76601)
Lot of low frequency coherence
Looking at last night lock stretch [1395051437, 1800 seconds]
https://ldas-jobs.ligo-wa.caltech.edu/~gabriele.vajente/bruco_1395051437_GDS_CALIB/
Lot of coherence with CHARD_Y, maybe a consequence of 76541
Lot of coherence with MICH and PRCL. and SRCL. What changed in the feed forward?
Images attached to this report
Comments related to this report
Another BruCo using last night Observing mode period: https://ldas-jobs.ligo-wa.caltech.edu/~gabriele.vajente/bruco_1395052218_GDS_CALIB/
Results are similar, so it was not due to some bad period. There is high coherence with PRCL too: either that's due to MICH cross coupling, or as Elenna suggests there might be something wrong with PRCL that also increases the CHARD noise (we saw in the past that CHARD noise increased when PRCL optical gain dropped)