TJ, Sheila, Keita

The LSC loop we use for locking the IR laser to the X arm is not great, (it doesn't have much gain margin which causes problems locking with different alignments.)

Nutsinee, Travis, and TJ have all run into trouble with the input aling step of initial alingment, where they could keep the arm locked on IR but the WFS would misalign the beam.  Today we looked at the signals, saw that they were oscillating at around 126 Hz for alignments that increased the transmitted power.  This was because the length loop was oscillating.  We were able to temporarily fix this by reducing the gain in the loop from 0.1 to 0.05.  We should take some time to reshape this loop.