Reports until 18:16, Tuesday 10 September 2024
H1 SQZ
victoriaa.xu@LIGO.ORG - posted 18:16, Tuesday 10 September 2024 (80031)
Re-aligned SQZ after SR3 move

Naoki, Vicky

We are back to observing after the SR3 move. For SQZ, we had to move quite a lot to get the SQZ LO loop to lock (Naoki mostly moved ZM5 yaw sliders around +200 urad).

PSAMS SDFs attached to get back to our recent values (not the single-bounce values we found this morning in lho80010, but what we used yesterday / last couple weeks). So ZM 4,5 strains = +5.5V, -0.8V as they were yesterday.

We weren't able to try these new values properly in full lock because

1) OPO TEC temperature was off, Naoki had to move the OPO TEC setpoint from 31.474 --> 31.457 (ie, lowered it by 0.017 degC). Noticed this because anti-squeezing was like 2-3 dB too low.
2) SR3 move meant a big alignment shift for SQZ, regardless of PSAMS settings. The new SCAN_ALIGNMENT plots now also include OMC_RF3_Q so we can compare whether this is a usable signal for SQZ ASC.

So now we're basically back to where we were this morning, after the sr3 move. We can try the single-bounce psams settings from lho80010 in full lock another time.

Images attached to this report