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Reports until 14:52, Tuesday 24 November 2015
H1 General (OpsInfo)
cheryl.vorvick@LIGO.ORG - posted 14:52, Tuesday 24 November 2015 - last comment - 14:59, Tuesday 24 November 2015(23706)
Ops Day Shift - Mid-shift Update: Maintenance ended, IFO required an initial alignment, Y arm / ETMY had issues, twice

Title: Ops Day Shift - Mid-shift Update, 22:22UTC

State of H1: lock in DRMI when I started my alog, now in Low Noise

Assistance: Kiwamu, Jenne, Ed

Summary: Y arm alignment has been very sensitive to ETMY alignment, and has needed special attention a couple times today.

Details:

In locking the arms in green, after maintenance, I was able to get Y arm to 0.85 in power, but that alignment was not good for green WFS, so killed the arm.

I chased the changing alignment every time WFS engaged even briefly.

Kiwamu and Jenne diagnosed this as a WFS issue, and driving the WFS issue is was a misalignment in ETMY.

I was able to get the power in the Y arm up to 0.85, however that was optomized for a beam path in the Y arm that wasn't what the WFS wants.

After the Y arm green alignment / locking was corrected and WFS engaged, I offloaded the green WFS and started an initial alignment.

After the initial alignment was complete, the Y arm was again an issue, locking at 0.4.

Again Kiwamu alighned the Y arm, and this time using only ETMY, and arm powers and WFS centering were good.

OMC needed it's WFS cleared.

ISS Second Loop needed to be engaged by hand.

I continued the locking, and currently the IFO is in Low Noise.

Comments related to this report
cheryl.vorvick@LIGO.ORG - 14:59, Tuesday 24 November 2015 (23707)Lockloss, OpsInfo

- IM1 was found to be not damped, aligned but not damped, and the damping was re-engaged while in Low Noise and the lock survived.

This was a error state that occured after I had all IMs undamped earlier today.  Not sure why Guardian didn't re-engage the damping. I only used Guardian to control the IMs, so it seems possible that there's an issue with commands for IM1.  This should be tested.

- 22:58UTC, Low Noise lock loss - IFO was oscillating and JeffK tried to intervene, however an earthquake arrived and broke the lock.

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