J. Kissel In order to prepare for implementing ECR ECR E2400330 which improves the whitening within the UK sat amps to improve the OSEM signal chain's total sensor noise between 0.05 and 10 Hz (see CSWG:11249 for a model of the noise improvement), I want to be sure we have a up-to-date measurement of the damping loop's suppression. This is so it can be divided out from the estimate of sensor noise before vs. after the change. Also, in general, it's good it we have pre-tuned templates for open loop gain transfer functions, as they use a markedly different excitation than "standard" "health check" transfer functions because the excitation must go through the damping loop controller filter. Note: if we compensate for the change in satamp frequency response well (with the anti-whitening filters in the OSEMINF banks), then the open loop gain / loop suppression / close loop gain should remain unchanged across the whitening filter change, so one we have these we shouldn't need to take them again (unless commissioning demands more changes to the filters). Since this kind of inventory is best done digitally for other folks reference and in case I have to delegate, I share it here. The following is a table of available and believed "should be the same as now" open loop gain TF templates and aLOGs for all suspensions with UK satellite amplifiers (and the Filter Cavity HSTSs FC1 and FC2 for good measure). Where there isn't templates that are "still valid," I give a brief note as to why. Optic aLOG Templates Still Valid? If not, why not? ETMX M0 (n/a) none NO *Never measured ETMX R0 (n/a) none NO *Never measured ETMY M0 LHO:6933 2013-07-??_????_H1SUSETMY_M0_*_WhiteNoise_OLGTF.xml NO *Way old, not enough DOFs ETMY R0 LHO:68405 2023-04-04_1731_H1SUSETMY_R0_WhiteNoise_*_0p01to50Hz_OpenLoopGainTF.xml Yes *But would be good to remeasure w/ and w/o R0 tracking ITMX M0 LHO:7720 2013-09-10_2306_H1SUSITMY_M0_[R,V]_WhiteNoise_OLGTF.xml NO *Way old, not enough DOFs ITMX R0 (n/a) none NO *Never measured ITMY M0 (n/a) none NO *Never measured ITMY R0 (n/a) none NO *Never measured TMSX (n/a) none NO *Never measured TMSY LHO:6654 2013-06-06_1511_H1SUSTMSY_M1_[L,P]_WhiteNoise_OLGTF.xml NO *Only L and P measured BS LHO:71269 2023-07-12_2000_H1SUSBS_M1_CDBIOState_1_WhiteNoise_*_0p01to50Hz_OpenLoopGainTF.xml Yes *Oplev Damping OFF LHO:71465 2023-07-18_1740_H1SUSBS_M1_CDBIOState_1_OLDampingON_WhiteNoise_*_0p01to50Hz_OpenLoopGainTF.xml Yes *Oplev Damping ON MC1 LHO:85291 2022-10-13_1900_H1SUSMC1_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml Yes MC2 LHO:85291 2022-10-13_1900_H1SUSMC1_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml Yes MC3 (n/a) none NO PRM LHO:85292 2022-10-13_1900_H1SUSMC1_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml NO *EPICs gains changed since PR2 LHO:85292 2022-10-12_2020_H1SUSPR2_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml NO *EPICs gains changed since PR3 LHO:64152 2022-07-26_1820_H1SUSPR3_M1_WhiteNoise_*_0p02to50Hz_OpenLoopGainTF.xml Yes SRM LHO:85285 2025-06-24_1704_H1SUSSRM_M1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF.xml NO *EPICs gains changed since SR2 LHO:65314 2022-10-13_1900_H1SUSMC1_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml NO *EPICs gains changed since SR3 LHO:85255 2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_*_0p02to50Hz_OpenLoopGainTF.xml Yes FC1 LHO:85290 2022-10-14_2330_H1SUSFC1_M1_CDBIOState_1_WhiteNoise_*_0p01to100Hz_OpenLoopGainTF_new.xml Yes FC2 (n/a) none NO OMC LHO:60054 2021-09-28_1640_H1SUSOMC_M1_WhiteNoise_*_0p02to50Hz_OpenLoopGain_2014vs2021Designs.xml Yes IM1 LHO:64039 2022-07-19_H1SUSIM1_M1_WhiteNoise_*_OLG.xml Yes IM2 LHO:64039 2022-07-19_H1SUSIM2_M1_WhiteNoise_*_OLG.xml Yes IM3 LHO:64039 2022-07-19_H1SUSIM3_M1_WhiteNoise_*_OLG.xml Yes IM4 LHO:64039 2022-07-19_H1SUSIM4_M1_WhiteNoise_*_OLG.xml Yes So -- to we really need to focus our measurement energy on the QUADs which have really never been characterized and the recycling cavity HSTS which have their EPICs gains changed in 2023. The good news is that 2023 me tuned a full set of QUAD R0 open loop gain TF templates using ETMY, so these templates should be viable for both the rest of the R0 chains as well as the main chain with little-to-no tuning (assuming alignment biases are not eating up a different amount of DAC range). That leaves on the TMTS not having tuned templates, so that's where we'll have to spend our tuning time. We obviously have templates that will work for the missing / out-of-date HSTSs. I'll begin the campaign during upcoming Tuesdays, in advance of making the ECR E2400330 change.