aLIGO LHO Logbook

H1 CAL (DetChar, ISC, OpsInfo)

jeffrey.kissel@LIGO.ORG - posted 10:20, Thursday 22 June 2023 - last comment - 10:35, Thursday 22 June 2023(70724)

Turned OFF CAL_AWG_LINES 2023-06-22 17:15:30 UTC

J. Kissel

While the LSC FF team stopped the observation segment, I took the opportunity to turn OFF the CAL_AWG_LINES 8 extra calibration lines.

If we lose lock again, either operator corps or I will turn them back on at the start of lock reacquisition. Again, the idea is to get ~4 or 5 clean lock acquisition stretches, so we assemble a good inventory to create a statistically sound model of the 60W thermalization (while acknowledging that clean*er* data is more valuable than getting high-number statistics).

Comments related to this report

jeffrey.kissel@LIGO.ORG - 10:35, Thursday 22 June 2023 (70726)CDS, DetChar, GRD, OpsInfo

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OK, *really* turned OFF all lines at 2023-06-22 17:24:34 UTC
J. Kissel, E. Capote 

Elenna reported from afar that she still saw excitations running from the LSC-DARM1_EXC point, and sure enough -- somehow -- the CAL_AWG_LINES guardian had not properly ramped off the four DARM EXC calibration lines. YUCK.

I re-cycled the guardian through LINES_ON then back to IDLE. This turned on, then turned off BOTH PCAL and DARM excitations cleanly as expected.
Gross!

Warning, TJ, "I told you so" bells are going off in my head: he had been cautioning my all through out the engineering run that the long term stability of these python / guardian / awg calls are suspect... I don't even know how to start investigating, so I tag CDS and GRD in hopes there are folks out there that can help diagnose and solve these stale test point control issues.