The DARM open loop consistently show a decrepancy between our DARM model at a few percent level. Inspecting the past four measurements (Aug-26, Aug-28, Aug-29 and Sep-08), I found that all of them show the same behavior. Something is wrong.
I have two hypothesis in my mind:
- The way we measure the open loop is bad. For example, the excitation is too high and some part of the interferometer is not linearly responding or something.
- Something is wrong in our analysis code. For example, some mistakes or tyops somewhere.
In either way, the residual is smaller than what we are trying to achieve in terms of the calibration accuracy. So we will go ahead and update the CAL CS calibration filters to the latest without correcting this "DARM open loop descrepancy".
Attached:
The 1st four pdfs are the sensing function or DARM response measured by Pcal Y from different days. As shown, the residula looks typicaly residual.
The 2nd four pdfs are DARM open loop measurements. All of them shows similar behavior in the residuals
Some notes:
Additionally, I edited H1DARMOLGTFmodel_ER8.m so that it takes the mismatch in the whitening filters into account. This is something Darkhan tried but did not get a chance to complete (alog 21318). Now it is coded.
