This is an assessment of the IM-V transfer function after the condition explained in entry 8672.
The previous assessment was done were with the BF GAS at 0 and IM-V at 178 µm. They should both be zero simultaneously and we should investigate how we ended up with such a discrepancy.
I wanted to measure transfer functions with the IM and IRM in a different relative position, therefore, I moved the IM down with the BF fishing rod.
- I noticed that when the BF was at approximatelly at -30 µm the IM and the BF did not seem to move freely vertically. See first picture. It is shown that when the BF is above -30 µm the BF and IM seem to oscillate freely and when the BF goes back down to -31 µm they don't oscillate as expected.
- In those conditions (BF at -30 µm) I took the following transfer functions: IM-L, IM-T, IM-P and IM-R. They all look healthy, including the ones measured with the IM vertical OSEMS. The files are in /kagra/Dropbox/Subsystems/VIS/TypeBData/SRM/TF/Measurements/20190424/
- The IM-V and BF GAS don't look alright. See second and third pictures.
Items 2 and 3 suggest the problem may be in the BF and not IM or IRM.
At the end of the exercise I moved the BF back to zero and measured the BF and IM-V TFs again (see test1 files in the same directory). They look healthy.
