Investigation of the glitch in the MN oplev light source : Effect of the fiber collimator
I checked the additional of the glitch noise from the fiber collimator of the MN oplev light source.
1. Checked the time series data by using the PDA and another fiber collimator
Fig.1. showed the result, very stable.
2. Checked the time series data by using the PDA setting in front of IX MN YPL fiber collimator
Fig.2. showed the result, there are some low frequency fluctuation, but signal itself has no glitch.
At this time, I changed the status of fiber with various situation(extending the rotated fiber, setting the surface of the chamber), but noise level became larger.
Rotating near the light source is most stable, but I didn't know the exact answer.
3. (Today's) Final state of IX oplev(Fig.3.)
MN YPL oplev : using Toyama spared light source, rotating the fiber near the light source
MN YRT oplev : using original MN YRT light source, rotating the fiber near the light source
PF YPL oplev : using original PF YPL light source, rotating the fiber near the light source
Images attached to this report
I checked the long term stability of the IX MN YPL oplev SUM.
It seems quite stable compared from previous one.
There are some glitch like signal (like around 2d), there would be actual motion (Some temperature drift or slow SUM change)
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