2025/02/21 5:06:00 - 5:20:00 silent run
2025/02/21 5:20:00 - Mini shaker injection position 1
Excitation : K1:PEM-EXCITATION_MCF0_RACK_9_EXC
50 - 200 Hz, 1Hz resolution, 10 s in each measurement, 300 cnt
2025/02/21 5:51:00 - Mini shaker injection position 2
Excitation : K1:PEM-EXCITATION_MCF0_RACK_10_EXC
50 - 200 Hz, 1Hz resolution, 10 s in each measurement, 300 cnt
2025/02/21 6:22:00 - Mini shaker injection position 3
Excitation : K1:PEM-EXCITATION_MCF0_RACK_11_EXC
50 - 200 Hz, 1Hz resolution, 10 s in each measurement, 300 cnt
2025/02/21 6:53:00 - Mini shaker injection position 4
Excitation : K1:PEM-EXCITATION_MCF0_RACK_12_EXC
50 - 200 Hz, 1Hz resolution, 10 s in each measurement, 300 cnt
2025/02/21 7:23:00 - 7:45:30 silent run
2025/02/21 7:45:30 - Acoustic injection OMC shaker
Excitation : K1:PEM-EXCITATION_SR3_RACK_6_EXC
50 - 200 Hz, 1Hz resolution, 10 s in each measurement, 100 cnt
2025/02/21 8:18:00 - 8:23:00 Shaker injection IFI leg
Excitation : K1:PEM-EXCITATION_MCF0_RACK_1_EXC
128 Hz single sine, 100 cnt
2025/02/21 8:23:00 - 8:28:00 Shaker injection IFI leg
Excitation : K1:PEM-EXCITATION_MCF0_RACK_1_EXC
128 Hz single sine, 300 cnt
2025/02/21 8:28:00 - 8:33:00 Shaker injection IFI leg
Excitation : K1:PEM-EXCITATION_MCF0_RACK_1_EXC
128 Hz single sine, 1000 cnt
2025/02/21 8:34:00 - 8:44:00 mini shaker injection position 2
Excitation : K1:PEM-EXCITATION_MCF0_RACK_10_EXC
116 Hz single sine, 300 cnt
To investigate which channels are good slow witnesses to understand the sideband around the environmental noises, I tried to apply the Hilbert transform to the strain signal.
I analyzed this data:
2025/02/21 8:23:00 - 8:28:00 Shaker injection IFI leg
Excitation : K1:PEM-EXCITATION_MCF0_RACK_1_EXC
128 Hz single sine, 300 cnt
- Fig.1: ASD of the strain (
K1:CAL-CS_PROC_DARM_STRAIN_DBL_DQ) around the shaker injection frequency (128Hz). - Fig.2: Time series of the instantaneous amplitude and frequency for the strain signal.
- Fig.3: ASDs of them.
- Fig.4-11: Coherence and Bruco projection with remarkable channels
Other Bruco projection plots are here: https://gwdoc.icrr.u-tokyo.ac.jp/DocDB/0165/G2516533/002/128Hz-single-sine_300cnt.html
We summarized the results of the noise projection from shakes where placed on the IFI bellows legs to DARM.
All results can be summarized in JGWDoc16560.
Fig.1. the block diagram of the shaker around IFI
Fig.2. Summary of the noise projection from shaker 1-4 to DARM
Fig.3. 128 Hz shaker injection at the position 4, large frequency conversion signals can be seen
Fig.4. 128 Hz shaker injection at the position 1, compared from Fig.3., the noise around 128 Hz is large, but not so many frequency conversion signals
Fig.5. 117 Hz shaker injection at the position 2 (on the beam duct btw IFI and IMM chamber), this characteristic signals can be seen only in position 2
