aLIGO LHO Logbook

H1 General

corey.gray@LIGO.ORG - posted 09:43, Sunday 06 November 2016 - last comment - 10:31, Sunday 06 November 2016(31256)

3rd Lock Attempt So Far....Knock On Wood

For this current lock (15min so far):

Went for only 25W.
At DC Readout, I turned the ITM Ring Heaters ON & proceded with Guardian after a minute or so.
Once at Nominal Low Noise, have had a range hovering a little above 70Mpc.
Robert asked that I turn the ITM Ring Heaters OFF again---to avoid heating the optics.
Took Observatory Mode to COMMISSIONING.

Comments related to this report

corey.gray@LIGO.ORG - 10:31, Sunday 06 November 2016 (31257)

After 20 minutes, we dropped out of lock. (ITMy did not oscillate after.)

Seconds prior to the lockloss:

VERBAL noted that PI Mode 27 was ringing up---& it was ringing up super-fast.
Another possibly related effect was the the SRC 1 & 2 Pitch CONTROL signals were both trending up a few minutes before the PI Mode 27 started its ring up.
See attached StripTool!

Will attempt another lock with the ITM Ring Heaters OFF from the get-go.

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