The MC2 roll mode notch (FM6 in ISCINF) was left off overnight, resulting in a rung up 28Hz peak in MC_L, which was producing a huge signal in PRCL. Once on the peak slowly disapeard. PRMI locking is now quite reliable. However we still have relatively big power fluctuations. I recorded today's settings in a setup script: sballmer/tempfixes/setPRMI Really, this should be fed to a guardian.
I left the PRMI locked tonight.
PRMI stayed locked for 9h with only 1 lock loss in the middle. 1st lock: 2014/02/03 05:03:00 to 08:39:00 (duration 3h36min) 2nd lock: 2014/02/03 08:41:00 to 14:31:00 (duration 5h50min) All times UTC.
The coherence analysis using STAMP-PEM revealed strong correlation (0.5 Hz) between H1_SUS-ITMX_L3_OPLEV (YAW and PIT) and H1:ALS-X_ARM_IN1_DQ. The coherence plots produced by Patrick can be accessed from here. Josh did follow up studies confirming the presence of 0.5 Hz strucutre in ITMX oplev signals and also saw strong correlation between ITMX oplev and POPAIR signals. The coherence plots Josh made can be accessed from here.