Lockloss after 46h25 in NLN. 1372737707.
No obvious cause, DCPD saturation tag. DARM was the first loop to change attached plot.
NOISE_CLEAN reloaded as requested in 71124.
Back to NLN and Observing at 06:24UTC.
This lockloss has again rung up the violins again, 71063. 1h25m in OMC_WHITENING. ITMY was slowest to damp.
The last lock we had with low violins was the 42hr lock after Tuesday maintenance, 06/27 21UTC to 06/2915UTC. Search for things that changed during that time:
- During Tuesday maintenance: We changed OM2 TSAMs 70849 but no arm alignment changes seen 70886, ISS gain was increased 70895, OMC single bounce measurement was taken 70866
- During the long lock: Jenne adjusted the LSC input matrix 70919
- During 06/29 lock acquisition: We had issues with ALSX PLL 70951, 70959 and the revCav alignment was tweaked 70944.
All the modes (both 500Hz and kHz) have been damping down nicely in the last 6hrs of so (EY20 is still higher than expected and we don't have setting for it - have tried finding one few times but it needs more effort).
Daniel and Sheila note that the H1:FEC-8_ADC_OVERFLOW_0_{12,13} are from before the ADC was updated so the real OMC channels are not overflowing, this is just a relic and can be used to see OMC_DPDC being closer to saturating level, could equally see using H1:OMC-DCPD_{A,B}_WINDOW_{MIN,MAX}.
We checked that OMC gain settings were not changed on the 29th June.