1. f2f meeting peculiar feature at the FSR

2. Investigating fsr feature for lower PSL values

11. Numbers 1.9W into MC (noise level ~ 2.5*10-1 cts/√Hz)
f(kHz)
37.81
37.97
38.01
38.06
38.08
cts/√Hz
1.97
1.72
0.84
6.82
0.58
f(kHz)
37.81
37.97
38.01
38.06
38.08
38.10
cts/√Hz
12.22
5.06
4.71
14.69
2.80
2.70
ratio2-1
6.2
2.94
5.6
2.15
4.83
f(kHz)
37.81
37.97
38.01
38.06
38.08
38.10
cts/√Hz
15.21
10.61
4.68
26.91
2.55
5.32
ratio3-1
7.72
6.17
5.57
9.95
4.40

12. Fit at f=37.81kHz G(f) =N/(1-f2/f02 + i Q f/f0) where,
N a normalization factor
f0 a resonance
Q the quality factor at f0

13. Some (crazy?) thoughts
To improve modeling of the internal mass resonances and their contribution to the signal one could do:
Mirror excitation transfer function measurements to identify which resonances are contributed by which optics
Ring-down measurements on each resonance for a more accurate measure of the resonance frequency and Q
Finite element analysis modeling of the optics to determine the mode shape of the pertinent resonances and a comparison between theory and experiment