Silent run : before starting the acoustic injection test
run1:
5:40:00 - (JST), OMC area, 100 cnt, 50 - 900 Hz, 5 Hz resolution
run2:
6:17:00 - (JST), REFL area, 100 cnt, 50 - 900 Hz, 5 Hz resolution
run3:
6:55:00 - (JST), REFL area, 100 cnt, 200 - 400 Hz, 1 Hz resolution
run4:
7:38:00 - (JST), REFL area, 100 cnt, 50 - 200 Hz, 1 Hz resolution
run5:
8:09:00 - (JST), OMC area, 100 cnt, 50 - 100 Hz, 1 Hz resolution
Ref. Previous analysis in klog25694
All results are placed in here.
There are several interesting issue, but the detail would be reported after finishing the check of the results.
Here showed the comparison of the noise projection for OMC acoustic injection.
Obviously, the acoustic noise effect for 100 -300 in OMC area was reduced in current interferometer.
I checked the acoustic injection test (around the IFI) data on 2024-10-11, starting from 7:38 (swept sine 50-200Hz, df=1Hz)
The excesses in the strain signal are showing side-band-like shapes. So some nonlinear (bi-linear) coupling may exist.
I also projected the acoustic noize into the strain with the response function model (convolution of the sideband response)
For most frequencies, the projected acoustic noise can't explain the current sensitivity.
Especially, the 128Hz peak itself is not acoustic, even though wider acoustic noises exist just below it.
Also for the 200-400Hz swept sine on 2024-10-11, starting from 6:50 JST
