TITLE: 08/14 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 25mph Gusts, 16mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.12 μm/s
QUICK SUMMARY: H1 has been locked for 12.5 hours and observing since commissioning wrapped up this morning.
I noticed the ~500Hz violin mode peak is high in DARM and saw that indeed ITMX mode 2 is elevated and has been growing this entire lock stretch. It looks like the gain was never turned on for this mode, which happens if the monitor for a mode is low enough when the full power damping is turned on. Since the violin damping Guardian sees the mode is growing, it's constantly zeroing the gain in the damping filters, so we've been unable to turn on the nominal gain of -15. To fix this, we would have to take H1 out of observing, take the VIOLIN_DAMPING node to 'DAMPING_ON_SIMPLE', then back to 'DAMP_VILINS_FULL_POWER' so that the node resets its "node growing" checks and sees the mode needs damping. I plan to do this if either L1 drops out of observing or if the 500Hz peak on DARM gets up to 10-16 m/Hz-1/2