Gabriele, Sheila
Between the locks on June 3rd and June 4th, our LSC feedforward became mistuned (more dramatically than before). This might explain most of our range drop this week. We don't know why this happened, there aren't any known changes that occured, other than a stretch of windy days with poor locking.
This morning we were briefly locked in our "post April 24th alignment", and Gabriele walked me though doing the iterative feedforward measurements.
I've updated the README.txt in userapps/lsc/h1/scripts/feedforward with instructions for the iterative measurement:
go to NLN_CAL_MEAS
To turn off FF: SRCLFF1 (or MICHFF) to DARM: turn SRCLFF1 (or MICHFF) gain to zero, turn off the FF filter but leave the high pass on, turn off the input to SRCLFF1, set gain to 1. Run excitation with the SRCLFF template
SRCL to DARM: nominal configuration with MICH and SRCL FF on, in NLS_CAL_MEAS. Run the template for SRCL excitation
When you measure MICH to DARM you leave everything in nominal condition
When you measure SRCL to DARM you leave everything in nominal condition
When you measure SRCLFF to DARM you leave MICHFF in nominal condition, turn off SRCLFF as aboves
When you measure MICHFF to DARM you leave SRCLFF in nominal condition, turn off MICHFF as above
The measurements are checked in at userapps/lsc/h1/scripts/feedforward
SRCLFF_excitation_ETMYpum_2024_06_06.xml
NoLP_MICHFF_excitation_ETMYpum_June62024.xml
MICH_excitation_June62024.xml
SRCL_excitation_June62024.xml
Here are two fits that should improve MICH and SRCL FF
SRCL
zpk([-7.169784531472987+i*46.80222713776738;-7.169784531472987-i*46.80222713776738;-50.91705199165386+i*64.16016193457278;-50.91705199165386-i*64.16016193457278;-42.15501976438775-i*1098.232422972419;-42.15501976438775+i*1098.232422972419;-145.0093557348077-i*1089.461704122895;-145.0093557348077+i*1089.461704122895;-245.0829862689482+i*1107.79921936364;-245.0829862689482-i*1107.79921936364;-141.5739067943562;-144.9209247430132;-826.3641092498208;-852.1997030446448],[-2.881922149238943+i*32.00142415651089;-2.881922149238943-i*32.00142415651089;-39.6556740022373+i*916.0295759541193;-39.6556740022373-i*916.0295759541193;-230.3431403668346+i*2309.933027270674;-230.3431403668346-i*2309.933027270674;-39.76964022276446;-39.8605595541308;-39.89837525205524;-39.91157191605507;-40.46668526791298;-2581.144039450426;-2671.009338936645;-2738.495590062898],0.4767541992000439)
MICH
zpk([-0.1470884781758559+i*48.42475784167187;-0.1470884781758559-i*48.42475784167187;-24.82947443442181+i*50.41982768133377;-24.82947443442181-i*50.41982768133377;-1.195340221327271+i*60.10254083145923;-1.195340221327271-i*60.10254083145923;-0.8119687656946064+i*112.301511110354;-0.8119687656946064-i*112.301511110354;-94.78274149473425+i*118.9486474187639;-94.78274149473425-i*118.9486474187639;-307.5544495976067+i*199.6473319209523;-307.5544495976067-i*199.6473319209523;-365.1498461668634+i*797.5973180592285;-365.1498461668634-i*797.5973180592285;-264.514660945466+i*941.2100034065085;-264.514660945466-i*941.2100034065085;49.35448274331864;-185.3386536745414],[-1.619706160754901+i*48.82075959570737;-1.619706160754901-i*48.82075959570737;-1.342047624329135+i*59.97321034526349;-1.342047624329135-i*59.97321034526349;-0.7898795886248342+i*112.7249598047579;-0.7898795886248342-i*112.7249598047579;-310.8951954733114+i*592.1396997441478;-310.8951954733114-i*592.1396997441478;-167.320180125188+i*927.5461319412049;-167.320180125188-i*927.5461319412049;-33.94826038138513;-33.98691038181345;-34.44985837050922;-35.1231562638948;-189.8775386189932;-309.2218677305598;-375.827056617601;-1502.151637570457],-8.520785430534616)