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Reports until 06:49, Saturday 04 May 2019
H1 AOS
corey.gray@LIGO.ORG - posted 06:49, Saturday 04 May 2019 - last comment - 10:41, Saturday 04 May 2019(48975)
H1 Lockloss: ALSy Issues

Symptoms:

Comments related to this report
corey.gray@LIGO.ORG - 07:08, Saturday 04 May 2019 (48976)

I forgot about Jenne's note about changing AS_A_36 phase.  So I have done that, but it didn't address the ALSy issue.

Trending oplevs for ETMy & ITMy does show some big alignment changes.  I still wonder if this is related to a WFS issue.  Will steer optics back to see what this does.  

NOTE:  I have not seen this issue before with a Y-arm misalignment like this!

corey.gray@LIGO.ORG - 08:25, Saturday 04 May 2019 (48977)

Ed's here to save the day, but I'm trying to remember what I saw & did with ALSy.

Definitely saw ITMy & ETMy both shift their alignment!  (see attached to see ITMy/ETMy pit/yaw shifts & various things I did to bring  back).

Back Story:  

  • Lockloss after 42-hr lock.
  • For relocking, immediately saw Green Y was in la la land
    • No light on ALSy video!  AND ALS-C_TRY_A_LF_OUT was dead flat at zero!  So there was no flashing in the arm!
    • Issues on ALS Y Overview
      • Green WFS spots were visibly off 
      • CAM ITM PIT Error signal was way above -0.2 (it was -1.2!).  On Jenne's old trouble-shooting document, it send to hit to hit Clear History button on the ALS Y Overview screen (but this button no longer seems to work....the clear history command/script/file is no longer in there)
    • Trended ETMy & ITMy and they shifted alot after the lockloss!
      • Because of ALS Y Overview issues due to WFS noted above, I was worried the issue was there, but since I couldn't fix anything with that, I started with moving optics.
    • Moved ETMy & ITMy back to pointing during the lock.  This finally gave baby flashes for ALS TRY.  
      • Oh!  Around this point is where I remembered to run the command Jenne alogged about on Thurs!
    • Walked ETMy, ITMy, & TMSy (by alot!) over several iterations.  Eventually had flashes over 1.0. 
    • Locked up ALS-Y (and finally gave ALSx attention).
    • Tried locking, but "IR was not found"
      • Ed came in and he found IR, but PRMI flashes looked UGLY!  He is now running an INITIAL ALIGNMENT.
Images attached to this comment
corey.gray@LIGO.ORG - 10:41, Saturday 04 May 2019 (48980)

Wanted to also mention that I clicked on the "Clear History" for each of the individual Filter Banks on the  ALS Y Overview (which I assume the non-functioning yellow Clear History button would do on this medm window).  When I did this I did not notice any change to the CAM ITM PIT Error signal.  These filter banks had their inputs OFF and their outputs were zero.  Just wanted to note that I did click their Clear Histories though.

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