[Manasa, Koji, Jenne]
We went into the BS and IOO chambers, and aligned the green beams such that they came out of the vacuum chamber. The idea here was to get the beams at the same height, but slightly offset in yaw. This required moving the Periscope on BS table, PBS in front of that periscope, the Periscope on the IOO table, and 2 steering mirrors on the IOO table after the 2nd periscope. The tables were not releveled, although we have aligned the full interferometer to this situation, so we do not want to touch the tables. The MC spot positions are still consistent with those measured earlier this afternoon, before this work, so I'm not concerned.
We confirmed that both green beams are hitting a good place (centered in pitch, and just left and right of center in yaw) on the mirror in the OMC chamber, and are getting to the center of the first mirror on the PSL table. We then coarsely aligned the beams on the PSL table.
We then relocked and aligned the arms for IR, and checked that the AS beam is centered on the mirrors in the BS chamber, and that the beam is coming out, and to the AS table. I touched the last mirror before PZT3 a small amount in yaw, and then PZT3 in pitch and yaw, until we saw the beam recentered on the first mirror on the AS table. At that point, we were also back to the center of the AS camera (which is good, since Koji had aligned all of that the other day). So, the AS beam is good.
We checked IPPOS, and have centered the beam on all the mirrors, and aligned the beam onto the QPD.
We checked IPANG, by looking through the viewports at the mirrors in the ETMY chamber. We are now centered in yaw, but clipping a bit low. This is what we want, since we always end up drifting high during the pump-down.
We see a nice, unclipped REFL beam on the camera.
We see a beam a little high on the POP camera, but Koji looked on the table with a card, and saw the beam....we just need to do minor alignment on the out of vac mirrors.
We checked again that the green TEM00 beams from both arms come to the PSL table.
We are getting POX and POY out, since we are using them to lock and align the arms.
Manasa and Koji recovered one clean allen key from the bottom of the chambers, but one remains, as a sacrifice to the vacuum gods.
I believe that, with the exception of checking the oplevs and taking photos of PR3, and the green steering optics, we have finished all of our vent tasks. We should do a quickie alignment on Monday, check the oplevs, take some photos, and put on the heavy doors. Pumping can start either Monday afternoon or Tuesday morning.
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