Back in August 2023 the damping gains for SR3 were reduced from -1 down(up?) to -0.5 to help with noise in DARM (72130). Since that change, we had never taken a set of transfer functions with the damping loops on with these new gains, so today I took those. The resulting transfer functions don't show too much damping, which is expected.
The data can be found in ../HLTS/H1/SR3/SAGM1/Data/2025-04-15_2000_H1SUSSR3_M1_WhiteNoise_{L,T,V,R,P,Y}_0p01to50Hz.xml, and has been committed to svn as r12228.
The results can be found in ../HLTS/H1/SR3/SAGM1/Results/ as 2025-04-15_2000_H1SUSSR3_M1_ALL_TFs.pdf and 2025-04-15_2000_H1SUSSR3_M1.mat, and have been committed to the svn as r12229.
Linking analysis pdf showing cross coupling between all DOFs
Also adding a comparison between this measurement and the last time that we took damped transfer functions since those previous measurements would have been taken with a different set of damping gains.
The last time a damped measurement was taken was back in 2015, and those transfer functions look a lot different than the model and this recent measurement, so I also looked at the next previous damped measurement, from 2014. This one was in phase 2b, so not in chamber, but here at least we see that these damped measurements match up pretty well both with the model and with the recent measurement.
This PDF along with a zoomed in version of some of the plots can be found at /ligo/svncommon/SusSVN/sus/trunk/HLTS/Common/Data/ as
allhltss_DampingOnComparison_H1SUSSR3_M1_Apr25vsFeb15vsMar14_ALL_TFs.pdf
allhltss_DampingOnComparison_H1SUSSR3_M1_Apr25vsFeb15vsMar14_ALL_ZOOMED_TFs.pdf
and have been committed as r12251.