J. Kissel, J. Warner

Jim and I hammered the H1 PCAL EY Periscope this morning after all planned modifications have been completed (as of LHO aLOG 40777). Excellent news -- all resonances below 400 Hz have been entirely squashed. Given these results, I would expect higher frequency resonances are equally squashed.

Nice work design and installation teams!

The attached images show the chosen accelerometer locations (different from LHO aLOG 40330 because both accelerometer mounting holes were used up by the baffle installation) and hit locations.

The .pdf attached shows four plots: 
- A recap of what we used to have at H1 and L1,
- A before vs. after comparison of the 12 O'Clock position accelerometer response to a 7 O'Clock strike
- A before vs. after comparison of the 3 O'Clock vs. 9 O'Clock position to 7 O'Clock strike (because of the cylindrical symmetry, we figured 9 and 3 were equivalent, as long as the radial position was the same-ish).
- A show of both 12 and 9 O'Clock responses to 7 O'Clock strike in the final configuration, showing there isn't an high-Q resonance left to be found!