We wanted to inject frequency noise lines to track the coupling to DARM during some TCS tests planned for tonight.
Craig and I commented out the 9MHz AM injection from the AWG_lines guardian, so we are currently only injecting two frequency noise lines at 74.7 Hz and 4.5 kHz.
We took the guardian to INJECTING and it worked first time, so we are leaving it here for now. If the lines are hindering science, they can be turned off by taking the AWG_LINES guardian to IDLE.
I also un-commented line 270 friom ISC_GEN_STATES gen_NOMINAL_LOW_NOISE, so when we go from NLN_CAL_MEAS back to NOMINAL_LOW_NOISE the lines will be switched back on. (When we go to NLN_CAL_MEAS the AWG_LINES guardian gets taken to idle, through STOP_INJECTING)
We changed the guardian to instead inject 3 frequency noise lines
- 25.2 Hz - low frequency where frequency noise is closest to DARM
- 201 Hz and 4.5 kHz to monitor the frequency noise to DARM coupling in the two other bands.
As well as 3 LSC lines, since Craig and Dan are curious about the PRCL UGF during our CO2 steps. I put the lines at:
- 35.3 Hz (PRCL)
- 38.1 Hz (SRCL)
- 40.7 Hz (MICH)
So don't be alarmed if you come in tomorrow and DARM is looking especially liney.
As of writing we're locked with a lower DARM offset to prevent the violins from saturating the DCPDs, I think this shouldn't really affect the TCS tests planned for tonight.
I added a line in the ISC_LOCK DAMP_BOUNCE state to request AWG_LINES to go to INJECTING, while we look at couplings for a few locks. We can comment it out / remove it later.
Craig and I added intensity noise lines to the AWG_LINES guardian in preparation for tomorrow night's ring heater change. The lines are at 47.3 Hz, 222 Hz and 4222 Hz. To get this working we added a ling to the AWG_LINES guardian which turns off the ISS 10Hz pole, when the injections are switched off this pole is re-engaged.
I don't think this will be a problem re-acquiring, but if there are locklosses from DAMP_BOUNCE where these lines are first engaged, or LASER_NOISE_SUPPRESSION or NLN then maybe there is something unforeseen in the intensity noise lines.
I also reduced the magnitude of the 35.3 Hz PRCL line because it seemed unnecessarily loud.
I have moved the 201 Hz frequency noise line to 203 Hz line so it's not as annoying line hunters (who are looking at 200.1 Hz).