VIS (EY)masayuki.nakano - 19:05 Thursday 06 February 2020 (12824)
Print this reportETMY oplev control contribution improvement
I put several notch filters and the sensitivity was improved at 30 Hz, and 60 Hz.
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masayuki.nakano - 5:16 Friday 07 February 2020 (12825)
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Added notches at 7.5 Hz and 15 Hz in the F0 GAS DAMP filter, and It reduced the peaks not only one of 7.5 Hz and 15 Hz but also most of the peaks around 10 Hz. They might be the side lobes of 7.5 Hz.
We have coherence with ITMX MN oplev and ETMX TM oplev PIT. The notches at those filters might improve the low-frequency noises. Please try it.
For oplev notches, you should use a common servo filter (TM_SERVO)
Low noise peaks should be damped, although the inspiral range will not be improved. They helps the actuator or sensor range for DARM.