Vicky, Austin, Camilla. Follows yesterdays alog 62089. Summary: aligned but weren't able to see any baffles and beam is smaller than ideal.
Austin and I measured distances between optics (all measurements attached and key ones below):
| INCHES | mm | |
| L3 to L2 | 41 | 1041 |
| L2 to L1 | 21 | 533 |
| L1 to LPM | 60 | 1524 |
| HWS to L3 | 58 | 1473 |
We started with translation stages at: Collimating lens @ 1.44; HWS:L2 @ 12.39. Later Vicky and I moved the L2 on it's translation stage upstream ~ 1.5" (starting location attached).
Vicky and I realigned the beam to remove the majority of the ITM reflection. Once we were finished and ETM was misaligned we could still see faint rings reflected off ITMX (that moved when ITMX adjusted) photo here. So more alignment could be done to get rid of those. We adjusted the CCD camera to try nd focus better but didn't see a difference so replaced in original position.
We adjusted the collimating lens and L2 to try and get the retro-reflected beam at the iris after ALS-M11 D1800270 to be a similar size as the outgoing beam - it is ~ double the size which is the best we could get with the 40mm collimating lens. The waist of the beam is still just after L3.
Adjusted wave plate to maximize beam to LPM from 270 to 292. This might have been the cause of reflected beam streaks we see on the camera. In the final image.
Final beam after yesterday is attached. It still seems to small to me so maybe we need to go back to the 50mm lens. Once we are happy we need to dither the ETM to measure the magnification.
From a controls tmux session on zotws24 I'm running a ETMX 0.5W ring heater test 2am-4am. Script will close ALS EX, EY shutters at the start. >> python3 /opt/rtcds/userapps/release/tcs/common/scripts/power_adj_scripts/ring_heater_schedule_shutterALS.py ETMX -s 1330941618 -d 2 -p 0.5" Robert will shutter ALS and when he turns the ring heaters back to thier nominal O3 values tonight.
This morning I replaced the Hartmann plate but didn't track down the source of the scattered light shown in alog 62121 photo yet.
The baffle is a 190mm circular aperture that should appear around 9.3mm in diameter on the HWS camera (assuming magnification of ~20.5X) - see aLOG 60937.
The aperture that appears in the HWS images looks plausible as the baffle shadow.
The ring heater test doesn't look like it's showing us anything much see attached. The spherical power is noisy and doesn't show any change. The TOTAL_PIXEL_VALUE does decrease.
