Displaying report 1-1 of 1.
Reports until 10:25, Monday 27 November 2023
H1 SQZ (DetChar)
sheila.dwyer@LIGO.ORG - posted 10:25, Monday 27 November 2023 - last comment - 08:56, Tuesday 28 November 2023(74428)
SQZ angle adjustment running in observe

Sheila, Camilla, Jenne, Austin

We droped out of observe for a few minutes to start running the sqz angle adjustment guardian state using the ADF that Naoki wrote on Wed (74376).  This changed the sqz angle by a few degrees in the first 2 minutes it was on, which improved the sqz blrms slightly.  

Because Vicky put some code in ISC_LOCK that set the SQZ_MANAGER request to it's nominal state, the only change we had to make was to change the nominal state of SQZ_MANAGER, and this should now be used in future locks. The new SQZ_MANAGER state is ADJUST_SQZ_ANG_ADF state number 110

 

Images attached to this report
Comments related to this report
sheila.dwyer@LIGO.ORG - 14:42, Monday 27 November 2023 (74431)

After several hours this still seems to be working, and our SQZ BLRMS have been stably a little better. 

Images attached to this comment
camilla.compton@LIGO.ORG - 08:56, Tuesday 28 November 2023 (74442)

We had two IFO re-locks last night with this servo running, plot attached. Comparing the first 2 hours of the lock with the servo running and without, the yellow and green BLRMS 300-1000Hz are more stable and lower with the new servo, this is great! Purple (4.6kHz) also improves more quickly.

The IFO range is still changing over the first hour of the lock but this is expected as the IFO thermalizes and may be less than the 1h30-2h we were seeing without the servo. Maybe the ADF RMS changing can tell us something about this.

Images attached to this comment
Displaying report 1-1 of 1.