alan.weinstein@LIGO.ORG - posted 12:21, Monday 16 December 2019 - last comment - 07:54, Tuesday 17 December 2019(53923)
DQ shift report December 9 - December 15
LHO completes 113+ hour lock stretch! With only brief periods outside of observing mode, ending for Tuesday maintenance (shortly after 1260000000 turn-over): alog 53781 , alog 53788
PSL chiller leak brought down the PSL for much of Wednesday (~16 hours) - alog 53831, alog 53846
Range: Steady at 110-115 Mpc throughout observing time.
ETMY violin modes 18 & 20 (at 1kHz) were ringing up; much effort put into damping them. It produced lots of omicron glitches at 1 kHz, through Wednesday Dec 11. Much reduced after PSL chiller recovery.
Lock stretches on Thursday through Saturday (Dec 12-14) had greatly elevated noise and glitchiness in the 20-35 Hz band (around ASC dither system (ADS) lines), associated with high microseism -induced scattering arches.
Lock losses on Thursday, Friday and Saturday; cause unknown. Lock loss on Sunday due to mag 6.9 EQ in Phillipines. All four recovered low noise in ~2 hours.
Readout of squeezer BP3 (500-900 Hz) still corrupted by excess noise.
Four CBC public alerts, two were retracted. S191215w is a nice BBH.
"ETMY violin modes 18 & 20 (at 1kHz) were ringing up; much effort put into damping them. It produced lots of omicron glitches at 1 kHz, through Wednesday Dec 11. Much reduced after PSL chiller recovery."
ETMY violin mode damping of modes 18 and 20 was completed early on Friday, Dec. 13th (Pacific), alog 53875.
Expanding on this comment:
ETMY violin mode damping of modes 18 and 20 was completed early on Friday, Dec. 13th (Pacific), alog 53875.