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Reports until 11:36, Thursday 22 February 2018
H1 SUS (AOS, ISC, SUS)
keita.kawabe@LIGO.ORG - posted 11:36, Thursday 22 February 2018 - last comment - 12:34, Thursday 22 February 2018(40663)
Using another beam on EY OPLEV restores ALS retro-reflection (Georgia, Betsy, Keita)

After Betsy's observation that a wrong beam might have been used for EY oplev (alog 40653), she and Georgia went into the chamber and faked the "correct" EY alignment by pushing the optic using EQ stops until the right beam is on oplev. It's not quite centered but it's not very far. The OPLEV SUM dropped to about 11k.

After this we turned on the ALS laser, and got retro-reflection well within the adjustment range of TMS OSEM. It seems like Betsy found the right beam for EY oplev.

When the REFL was on ALS REFL PD, TMS sliders were P=-88 urad, Y=-168 urad (full range is +-298 for P, +-608 for Y).

Rick and Travis are going back to EY to see if this EY angle is also better for PCAL. IF that's the case EY needs to be properly realigned (not faked by EQ stops but by adjusting the cage etc.).

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richard.savage@LIGO.ORG - 12:34, Thursday 22 February 2018 (40668)CAL

TravisS, RickS

We switched on the Pcal laser and checked the alignment of the two Pcal beams into the Rx module integrating sphere.

Both beams were reasonably well centered.  They were slightly offset from eachother vertically, but only by about 1-2 mm and they were very close to the center of the Rx integrating sphere aperture.

It seems that work on the periscope structure DID NOT impact the Pcal alignment significantly (GREAT NEWS!).

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