Reports until 11:13, Saturday 12 October 2019
H1 AOS
daniel.brown@LIGO.ORG - posted 11:13, Saturday 12 October 2019 - last comment - 01:35, Monday 14 October 2019(52443)
Phase camera installation work

Cao and I are on site to work on installing the phase camera on ISCT1, part of work permit 8389.

We'll be in and out off the OSB optics lab and in the LVEA around ISCT1. As we'll be needing the POP beam on the table we'll also need PRMI locked.

Comments related to this report
daniel.brown@LIGO.ORG - 22:12, Saturday 12 October 2019 (52445)

Cao and I are done for today

daniel.brown@LIGO.ORG - 11:02, Sunday 13 October 2019 (52446)

We are back in, we'll be around ISCT1 and the electronics room.

daniel.brown@LIGO.ORG - 01:35, Monday 14 October 2019 (52448)

Forgot to post when we left. 

This weekend we managed to get the majority of the phase camera setup installed onto ISCT1. We are aiming to image each sideband at the POP port to help diagnose what might be happening to all our RF sidebands at LHO.

The phase camera needs a reference light field to image each sideband. The phase camera we are installing is detailed in P1900013, we are compiling a technical note on the setup which I'll post when it's more complete. The reference field comes from a fiber from the ALS distribution box (sample port ~2.5mW) which couples light onto an optical breadboard next to ISCT1. This has two free space AOMs on it which are double passed and allow us to shift the reference field in frequency relative to the carrier. The shifted light is fiber coupled from the breadboard on to ISCT1 where we have aligned and mode-matched it to the beam at POP. Some of the combined light is sent to a photodiode and used to phase lock the beat with the electronics driving the phase camera. So far the phase locking is working and the phase camera is demodulating the beam. However, some of our electronics died just before the weekend and we weren't able to fix it, so we didn't manage to get an actual image yet. We've come up with a solution that we'll try tomorrow and hopefully start gettings images of the beams in PRMI/DRMI.