This afternoon we stepped CO2X up from 1.7W in to 2.5W input, with steps of +0.2W requested per 20 minutes. We had no squeezing during this time and no LSC feedforward during the last steps. Attached is scopes, DARM (increased noise at 20-50Hz is a glitch, not caused by CO2 change) and DARM at high frequency.
Circulating power in the X-arm increased plot and high frequency noise lowered plot with increased CO2X, but its hard to see any other effects.
Are CO2 Beams still well aligned to IFO? Unsure
Looking at when the CO2 beam is first turned on at POWER_25W plot compared to the IFO beam when it's just got to 60W input plot:
- ITMX CO2 - It's hard to see the as the point absorbers dominate the HWS signal.
- ITMY CO2 - CO2 looks down and right of IFO beam.
Last adjusted the CO2 alignment in 68391. Would like to check alignment in lock after CO2 beams have been on for a while as we have previously seen the CO2 alignment drift as the mirrors warm up.
