Oli, Keita, Elenna, Jennie, Sheila, Ryan S, Rahul, Betsy, Camilla
Day 1: 84193, Day 2: 84228, Day 3: 84230 and 84239, Day 4: 84274, Day 5: 84292
- To work on REFL beam: need PRM aligned and ITMX or ITMY misaligned
- To work on POP flashes: need PRM aligned and ITMX aligned
- To work on POP single bounce (low power ~30uW into HAM1 POP path for 20W from PSL): need PRM and ITMY misaligned
In the morning Keita and Jennie aligned the POP flashes on the periscope mirrors and M10 dichroic. The height of this beam is 3.75" on these mirrors to account for the ALS green beam being 13mm above the POP beam. Keita was a little concerned about the height of the top periscope mirror so we'll need to check the green ALS beam carefully on this and if it 's near clipping we may need some in-vac pico-ing.
Rahul then moved PM1 to it's final position. Elenna and Rahul checked that the signed of the PIT and YAW sliders were correct.
Shiela, Rahul and I then worked on centering the beam on PM1 and L2 without the 90/10 M12 in place, so that we could later have enough power to beam profile the POP single bounce beam. To get the beam height back up to 4" at PM1, Rahul needed to pitch PM1 mechanically.
Oli then increased PSL input power to 20W, we aligned to POP single bounce and Sheila and I took beam profile measurements before PM1 and after L2, details in 84307.
Elenna, Rahul and I then replaced the 90/10 M12 and recentered the beam on PM1 and L2. We started aligning the POP air path but aren't happy with it, dumped the beam and will continue to work on.
Betsy let in the PSL ALS beam into HAM1 by opening the light pipe and I dumped it straight away. See 84312.
Today we plan to: align the POP, REFL and PSL ALS beams out of the chamber, open the X-arm check the green ALS beam alignment on the shared optics and off the table, including rolling up ISCT1 and adding the VP simulator. The POP LSC/ASC diodes and all beam dumps still need to be aligned and checked.
Keita and Jennie's log on the work done in the morning is 84308.
Just adding a clarification. "Elenna and Rahul checked that the signed of the PIT and YAW sliders were correct. "
We confirmed that adding a positive pitch offset in the alignment slider of PM1 results in PM1 pitching downward, as expect in a right handed coordinate system, and verified by watching the beam reflecting off PM1 shifting down. We also confirmed that a positive yaw offset results in the optic rotating left (as seen from behind the optic), again as expected from the right handed coordinate system, and verified by watching the beam reflected off PM1 shifting left.
I went back and forth a few times with the offsets while Rahul held an indicator card in front of the optic to watch the beam move to see the response of PM1.