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VIS (PR3)

takafumi.ushiba - 10:57 Wednesday 07 February 2024 (28536)

Health check of PR3

I measured mecanical TFs of PR3 for health check.
Figure 1 - 33 show the result and all TFs seem good.
Followings are what I noticed.

1. BF GAS TF has a slightly low coherence at high frequency region.
2. Cross-coupling between different DoFs at IM stage is changed but It can probably be reduced by decoupling.

Images attached to this report

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Comments to this report:

takafumi.ushiba - 11:25 Wednesday 07 February 2024 (28537)

I put notches at GAS resonances not to excite the suspension too much and measured BF GAS TF again (fig1).
Coherence at high frequency becomes better and seems fine now.

Images attached to this comment

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