J. Driggers, S. Dwyer, J. Kissel, L. Sun

We have measured the full suite of calibration measurements today. After processing, they look of excellent quality, and we believe we understand all of the systematic error that we see. This systematic error is small enough, and impacting the overall response function uncertainty in various frequency regions in such a way that we are comfortable pushing this results to the front-end and updating the calibration.

Said again in less words: we are ready to update the front-end calibration (CAL-CS, CAL_DELTAL_EXTERNAL, etc.) with the results quoted below.

Status of systematic error
   - We have a prominent detuning below 20 Hz, and it's pro-spring. The fit to and implementation of compensation for a pro-spring is still in it's infancy, so it is under-reporting the frequency -- it's measured to be about 6.5 Hz, but the fit claims 3.7 Hz. The systematic error induced by this flaw is small above 20 Hz. 
   - The TST actuator stage is modeled quite perfectly. Little to no systematic error.
   - The PUM actuator systematic error remains below 20 Hz. We've identified that it's parasitic length drive not accounted for through L2A / A2L. This is prominent because the IFO spot positions on ETMX are -18 +/- 0.2 mm in pitch (-vertical) and 18 mm +/- 0.2 in yaw (+transverse) off from the center. (note for PCAL team -- ETMY spot positions: -17 +/- 0.2 mm (-vertical) and 7.5 +/- 0.2 mm (+transverse))
   - The UIM actuator systematic error starts to creep in around 50 Hz. This is understood to be the high frequency dynamics of the UIM BOSEM actuators, and we have measurements in the can to fix this, we just haven't yet had the time. As it stands, the impact of this error is smaller than other things, so it remains low on the priority list.

Lilli is working on estimating the overall uncertainty and systematic error that would result from these residual systematic errors from each stage -- see the start of this in LHO aLOG 47926. 

Here're the values we will use to update CAL-CS today.
Sensing Function
Optical Plant:
    Optical gain, H_c (ct/m)                 | 3.254e+06 (+3253,-2286)         or (+0.09994%,-0.07023%)
    Optical gain, H_c (mA/pm)                | 4.345     (+0.004343,-0.003052) or (+0.09994%,-0.07023%)
    Cavity pole, f_cc (Hz)                   | 410.5     (+1.156,-1.314)       or (+0.2816%,-0.3202%)
    Detuned SRC spring frequency, f_s (Hz)   | 3.744     (+0.0717,-0.07096)    or (+1.915%,-1.895%)
    Detuned SRC spring quality factor, Q_s   | 45.57     (+77.6,-123.2)        or (+58.72%,-36.99%)
    Residual time delay, tau_c (usec)        | 1.434     (+0.8076,-0.9042)     or (+56.32%,-63.06%)


The code spits out (filters for go in the H1:CAL-CS_DARM_ERR_Name08):
Inverse Sensing FOTON values: [NB: SRCD2N zpk gain based on sensing sign in parameters file]
    SRCD2N: zpk([410.6047;0.0000+3.7096j;0.0000-3.7887j],[0.1;0.1;7000],1,"n")gain(1405.76)
    Gain: gain(3.073e-07)

Inverse Sensing without cavity pole FOTON values for CFTD path: [NB: SRCD2N zpk gain based on sensing sign in parameters file]
    SRCD2N: zpk([0.0000+3.7096j;0.0000-3.7887j],[0.1;0.1],1,"n")gain(1405.76)
    Gain: gain(3.073e-07)

But these values (a) are unphysical, (b) incorrectly calculating the zeros for an anti-spring (a la LHO aLOG 31693), and (c) normalizing the gain of the filter at 500 Hz instead of 100 Hz. We'll fix this later. For now, we've just manually crafted the filter in foton, which has a complex zero at 3.744 Hz with a Q of 45.57,
    Normal Path -- SRCD2N: zpk([410.6047;0.0411+i*3.7438;0.0411-i*3.7438],[0.1;0.1;7000],1,"n")gain(1364.02)

    CFTD Path   -- SRCD2N: zpk([0.0411+i*3.7438;0.0411-i*3.7438],[0.1;0.1],1,"n")gain(1364.02)
These will be installed into H1:CAL-CS_DARM_ERR and H1:CAL-CS_DARM_CFTD_ERR filter banks in modules titled "O3_D2N" and "O3Gain".

Actuator
UIM
    Actuator gain, H_c (N/ct)              | 7.699e-08 (+2.588e-11,-2.585e-11) or (+0.03362%,-0.03357%)
    Residual time delay, tau_A (usec)      | 64.69     (+1.52,-1.513)          or (+2.35%,-2.339%)

PUM
    Actuator gain, H_c (N/ct)              | 6.118e-10 (+1.677e-13,-1.686e-13) or (+0.02742%,-0.02756%)
    Residual time delay, tau_A (usec)      | 2.088     (+0.9309,-0.9287)       or (+44.57%,-44.47%)

TST
    Actuator gain, H_c (N/ct)              | 4.739e-12 (+1.36e-15,-1.368e-15) or (+0.02869%,-0.02886%)
    Residual time delay, tau_A (usec)      | 7.474     (+0.542,-0.5453)       or (+7.252%,-7.297%)

These gains will be installed into the H1:CAL-CS_DARM_ANALOG_ETMX_[L1, L2, L3] banks, in modules titled "Npct_O3"

The pyDARM model parameters for this data set live here:
    ^/trunk/Runs/O3/H1/params/modelparams_H1_20190327.py

I'll post more details about processing scripts and where the data lives in a comment below.