Reports until 22:39, Friday 22 November 2024
H1 GRD
sheila.dwyer@LIGO.ORG - posted 22:39, Friday 22 November 2024 - last comment - 23:02, Friday 22 November 2024(81430)
some changes to TRANSITION_FROM_ETMX

Ryan had two locklosses from an oscillation just below 1 Hz that showed up in the SRCL error signal and CSOFT P (and a little less in yaw) this evening during the state TRANSITION_FROM_ETMX. 

I had a look at the state and found that there was a step where we were clearing histories repeatedly while waiting for the bias to reach 0, this probably wasn't the problem but I added and increment to the counter to stop doing this. 

Since the oscillation rings up very slowly, I lowered the bias ramp times from 60 seconds to 30 seconds.  This worked once, although I'm not sure it always will. 

We've now passed through that state and the guardian is waiting in OMC_WHITENING.  I will set it to automatically go into observing when the violins are low enough.

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sheila.dwyer@LIGO.ORG - 23:02, Friday 22 November 2024 (81431)

While waiting for the violins I had a look at SDF. 

There were a couple diffs from forcing the squeezer TTFSS to lock when the refernce cavity was unlocked, I've reverted those.

I am not sure what's going on with HAM4 ISI FF but I've accepted what's shown in the screenshot.

Vicky triggered on the SQZ ASC, she thinks it was working.  We lost lock for some reason while waiting for the violins.

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