As is apparent in alog 46530, DARM calibration is off by about 10% at 100Hz, and it's hard to make comparison between now and Dec 2018 as is until a good calibration model is made.
I made a FOM dtt template with two new calibrations, one starting December 08 2018 and the other Jan 01 2019.
/opt/rtcds/userapps/trunk/isc/h1/scripts/H1_DARM_FOM_PcalScanCorrected.xml
It should be OK for f>10Hz.
What I did:
From dtt, export CAL-DELTAL_EXTERNAL_DQ/CAL-PCALY_RX_PD_OUT_DQ transfer function of
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Measurements/FullIFOSensingTFs/
2019-01-16_H1_PCAL2DARM_TF_5t1100Hz_3min.xml
to a text file in /opt/rtcds/userapps/trunk/isc/h1/scripts/tempCalibForDtt20190123/.
Export the default TF calibration of the above transfer function to another text file.
Export the latest calibration of CAL-DELTAL_EXTERNAL_DQ dated 2018/10/4 22:28:48 from H1_DARM_FOM.xml to yet another text file.
Combine these three files and save into yet another file (newstopgapcal.txt) using
/opt/rtcds/userapps/trunk/isc/h1/scripts/tempCalibForDtt20190123/makeStopGapCalForDtt.m
Do the same for 2018-12-05_PCAL2DARM_TF_5t1100Hz_2min and save into yet another file (oldstopgapcal.txt).
Open DARM_FOM.xml using dtt.
Make a new calibration for H1:CAL_DELTAL_EXTERNAL_DQ at 2019 Jan 01 00:00:00.
Click "Trans. Func." tab, click "Edit", click "File" and "Open", load newstopgapcal.txt.
Repeat it, this time 2018 Dec 08 00:00:00, load oldstopgapcal.txt.
Save the dtt template as H1_DARM_FOM_PcalScanCorrected.xml
Here is a comparison of a lock from late last week (Jan 21 0:30 UTC) to the November reference using Ketia's template. The noise is generally similar, although if the November calibration was correct the shot noise has gotten slightly worse, when we increased the input power.
The november lock was Nov 11 at 21:39 UTC, the "live" lock is Jan 21 at 0:23 UTC. The power on the POP diode increased 22.7% from November to now, so the shot noise limited sensitivity should have improved by 10%. If this calibration comparison is really correct, we have instead lost sensitivity. It might be worth taking a closer look at the calibration lines in November to see how our optical gain compares.
I looked at the Nov 10th time that Sheila has in her DTT template (11th Nov as typed in the text of the log is a mis-type) and the 21st Jan time. The PSL injected power increased by 13% between these two times (26.7W -> 30.3W), and the POP_A_LF, and all 4 TR QPD sums all agree that the circulating power in the IFO increased by 10%. So, it's certainly true that the circulating power has increased. But, as Sheila points out in her plot, the shot noise region appears to have gotten worse. Sheila is doing a test right now to investigate this further.