It has been a struggle, but we have finally made it to Low Noise.

Locking Notes

Started out the morning not being able to lock the arms in green, it looked like symptoms of useism from the frequency of the arm power. Jim W and I tried many different configurations before settling on the original configuration that we started on. From there I was able to lock the Y arm in green, but the X arm would slowly decay with the WFS on. I tried realigning many different optics in the arm, as well as BS and PR3 to increase the COMM Beatnote, but nothing seemed to help.

I read Jenne's awesome guide and looked at the error signals and tried to get them all into an acceptable area. This is where I struggled. I could get DOF1 and 2 closer to 0 but then 3 would be way off, or another variation like that. I ended up just putting DOF1&2 close, but kept DOF3 far off (~0.6) and then turned on the WFS for the first two. From here I would move ITMX P a bit, then wait for the WFS to catch up, then move it some more, and then wait, then adjust PR3 for the beatnote, and repeat. The entire process was slow and sometimes looked like it was actually making things worse, but it eneded up working and I would hold Xarm in green with all WFS on.

The rest of initial alignment took time since everything seemed to be a bit misaligned, but made it through using only the tricks that are in our troubleshooting wiki.

Other Notes

h1build crashed this morning which brought down the beckhoff SDF. The CDS team is working on bringing it back up.

Weather is warming (~30F), which may make the ice conditions a bit more slippery. We will see.