J. Kissel, D. Tuyenbayev Following preliminary results from Darkhan on the individual actuation strength of the UIM and PUM stages for H1SUSETMY (see, thus far LHO aLOG 31275), and the current delightfully long lock stretch with them in place, I'm bringing this study to a close. I've turned off the temporary L1 and L2 calibration lines at 33.7 and 34.7 Hz, respectively. We do not intend on turning on these lines again for the duration of the run. These lines were turned OFF at Nov 07 2016 21:21:49 UTC.
Summary
A refined analysis of the L1, L2 and L3 stange actuation strenghts was done using the data from last several days that include several low-noise lock stretches. Actuation strength factors are:
KU = 8.020-8 +/- 2.983-10 N/ct ( std(KU) / |KU| = 0.0037 )
KP = 6.482-10 +/- 2.748-12 N/ct ( std(KP) / |KP| = 0.0033 )
KT = 4.260-12 +/- 1.313-14 N/ct ( std(KT) / |KT| = 0.0031 )
Details
Following 4 lines were used to calculate the factors: UIM (L1) line at 33.7 Hz, PUM (L2) line at 34.7 Hz, TST (L3) line at 35.9 Hz and PcalY line at 36.7 Hz. The most recent DARM model parameters were used for this analysis. Also, values past Nov 5 were calculated with the updated DARM filters (see LHO alog 31201), not accounting for this would produce results biased by 1-2%.
Each data point is a quantity calculated from 10s FFTs. The outliers were removed in two steps:
- took the mean and the standard deviation of all data points in intervals when the IFO range was >=50 MPC, removed 3-sigma outliers;
- removed the 3-sigma outliers from the mean of the remaining data points.
The mean values and the standard devitaions noted above were taken from GPS time interval [1162369920 1162413500], ~11 hours of low-noise data (blue markers). Standard errors on the mean values, std(Ki) / sqrt(N), are orders of magnitude smaller compared to the Pcal and the DARM loop model uncertainties (number of data points in the seletected interval - N=4251).
For preliminary results from Nov 4 data and before see related reports: 31183, 31275.
Recall the ER8/O1 values for these coefficients were
'Optic' 'Weighted Mean' '1-sigma Uncertainty' '1-sigma Uncertainty'
'Stage' '[N/ct]' '[N/ct]' '%'
'ETMY L1' '8.17e-08' '3.2e-09' '3.9'
'ETMY L2' '6.82e-10' '5.2e-13' '0.076'
'ETMY L3' '4.24e-12' '4.1e-15' '0.096'
from LHO aLOG 21280.
Comparing against numbers above,
KU = 8.020-8 +/- 2.983-10 N/ct ( std(KU) / |KU| = 0.0037 )
KP = 6.482-10 +/- 2.748-12 N/ct ( std(KP) / |KP| = 0.0033 )
KT = 4.260-12 +/- 1.313-14 N/ct ( std(KT) / |KT| = 0.0031 )
This means a change of
(ER8 - ER10)/ER8 =
ETMY L1 0.0183
ETMY L2 0.0495
ETMY L3 -0.0047
We will compare these numbers against those determined by frequency-dependent transfer functions, e.g. the to-be processed data from LHO aLOG 31303, and update the low-latency/ calibration accordingly next week. It will also be interesting to re-cast the L1 and L2 numbers into a combined actuation strength change from ER10/O1, and compare it against the constantly calculated kappa_PU and check consistency there.
Data points prior to DARM filter update mentioned in the report were analyzed with the help of following DARM model parameters:
ifoIndepFilename : ${CalSVN}/Runs/PreER10/Common/params/IFOindepParams.conf (r3519)
ifoDepFilename : ${CalSVN}/Runs/PreER10/H1/params/H1params.conf (r3640)
ifoMeasParams : ${CalSVN}/Runs/PreER10/H1/params/H1params_2016-10-13.conf (r3519)
and after the the DARM filters were updated (GPS 1162336667) the following configuration was used:
ifoIndepFilename : ${CalSVN}/Runs/PreER10/Common/params/IFOindepParams.conf (r3519)
ifoDepFilename : ${CalSVN}/Runs/PreER10/H1/params/H1params_since_1162336667.conf (r3640)
ifoMeasParams : ${CalSVN}/Runs/PreER10/H1/params/H1params_2016-10-13.conf (r3519)
Scripts were uploaded to CalSVN at
${CalSVN}/Runs/PreER10/H1/Scripts/Actuation/2016-11-08/
5 days SLM data (75 MB): ${CalSVN}/Runs/PreER10/H1/Measurements/Actuation/2016-11-08/
Plots: ${CalSVN}/Runs/PreER10/H1/Results/Actuation/2016-11-08_H1_UPT_act_strengths_*
We discovered that in the single-line analysis we had an incorrect sign for TST stage actuation (we incorrectly set the sign of the N/ct coefficient).
The updated results have been posted in LHO alog 31668.