As soon as we flipped the beam diverter open we got the REFL beam on ISCT1.
Then we went into HAM1 and noticed that the beam was moving by a huge amount in PIT. TTs were not damping at all. Turns out that that was a TT model problem. SUS people and Dave Barker are working on it.
We will resume our work when TTs are fixed, and in the mean time we'll look at the IFO alignment.
We made one measurement using NanoScan by misaligning the 50% BS after the HWP to direct the beam to the head. The BS and Nanoscan were approximately 8"x44" apart (give or take an inch).
| 1/e^2 (13.5%) diameter mean | stddev | Goodness of Gaussian fit mean | stddev | Profile Averages | |
| X (axis 1) | 3851.01 um | 1.982 um | 0.01 | 0.000 | 10 |
| Y (axis 2) | 3959.23 um | 1.232 um | 0.01 | 0.000 | 10 |
| 45 deg (axis 1) | 4117.74 | 1.475 | 0.02 | 0.000 | 10 |
| 45 deg (axis 2) | 3845.62 | 0.763 | 0.00 | 0.000 | 10 |
These are just the numbers NanoScan software dumped. As was partially captured by https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=8437, our experience is that Nanoscan, ModeMaster (takeing the beam size at the head) and hand-driven knife edge agree with each other within 10%.