The sensor correction is installed and ON on all the chambers, but with a nominal matching gain of 1.
I made a small script to calculate the correct matching gain for X, Y, Z. The script works only for the HAM-ISIs for now, but it will be pretty easy to adapt. What it does:
- Grab the ground seismometer and GS13 data in X, Y, Z.
- Calculate the ASDs and calibrate them in m/rt(Hz).
- Calculate the GS13 over Ground ratio.
- Take the mean of the ratio for a [0.1Hz 0.4Hz] bandwidth.
Before running this process, the ISI needs to be in High blend mode (750mHz) on all DOFs with sensor correction OFF.
I've done this exercise for HAM4-ISI. The numbers seem a little small (Gain for X: 0.8784, gain for Y: 0.8702, gain for Z: 0.8574) but brings some improvement (see plot attached).
This has been done during the day, we might want to do it overnight for better tuning.
I'll do the other chambers ASAP. The script that I made is for now commited in the HAM4 folder of the svn:
/ligo/svncommon/SeiSVN/seismic/HAM-ISI/H1/HAM4/Misc/gain_matching_calculation.m
After some feedback, I rearranged the script and commited it into:
/ligo/svncommon/SeiSVN/seismic/HAM-ISI/Common/Misc/HAM_gain_matching_calculation.m
What it does now:
HAM_gain_matching_calculation(IFO,Chamber,start_time,duration)
. Grab the ground seismometer and GS13 data in X, Y, Z from start_time to start_time+duration.
. Calculate and plot the calibrated TF between Ground and GS13
. Take the mean of the amplitude for a [0.1Hz and 0.4Hz] bandwidth
Remember. before running this process, the ISI needs to be in High blend mode (750mHz) on all DOFs with sensor correction OFF.
I put HAM4, 5, 6 in this configuration last night and calculated the new matching gains.
| HAM4 | HAM5 | HAM6 | |
| X | 0.8730 | 0.9280 | 0.96 |
| Y | 0.8619 | 0.9161 | 0.9496 |
| Z | 0.8487 | 0.9604 | 1.0189 |
I'll put this new numbers in the MEDM screens in a minute.