[Sheila, Jennie, Elenna]

Here are some notes about how we by-hand improved the OMC alignment

• Sheila centered the beam on AS_C using SR2 movements by hand
• Sheila ran AS centering loops for WFS A and B until the beam was centered, then turned them off
• we noticed half the range on the OMC suspension is in use on T2 and T3, so Jennie moved OMC sus in pitch to reduce the drive
• Jennie used OM2 for QPD B alignment, use OM3 for QPD A alignment- centered the beams on each QPD by walking the suspensions in pitch and yaw
• Sheila quote to explain the process further: "this is a screenshot I took after I moved OM2 yaw to center OMC QPD B and OM3 yaw for OMC QPD A, with the OMC suspension offsets small. This means that we are off center on the AS WFS DC, but I put offsets into them so that we could close the AS centering loops. Turning on the AS centering loops didn't suppress the 0.5 Hz motion much. Even though the QPDs are fairly close now before turning on the ASC loops, the OMC suspension still saturates in pitch when we turn them on."
• with sensor correction on, things improved because there was less movement overall in the beam
• the results of these movements are shown in the attached screenshot (this is the screenshot referenced in the quote above)
• Sheila successfully ran the OMC ASC and they converged without saturation
• Second screenshot shows the results of running OMC ASC
• I next pico-motored to center the beam on AS A and B in pitch and yaw
• Once I centered the beam, I engaged the DC3 and DC4 loops to check they would run without any issues. They ran just fine so I again turned them off and disabled the picomotor

As a final check I turned on both OMC ASC and AS WFS centering and the loops converged appropriately.