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Reports until 16:37, Tuesday 19 September 2017
H1 SEI (PSL)
hugh.radkins@LIGO.ORG - posted 16:37, Tuesday 19 September 2017 - last comment - 17:58, Tuesday 19 September 2017(38713)
SEI Progress on HAM2---DAMPING 80% Complete

All Damping installed on the HAM2 ISI for Corners 2 & 3 as well as the Horizontal GS13 Can Damping on Corner1.  Remainder is Corner1 Spring and Flexure dampers and the Vertical GS13 Can Damper.  Working with PSL on the ISS cabling which complicates the Corner1 work on the blade spring.

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jeffrey.kissel@LIGO.ORG - 17:58, Tuesday 19 September 2017 (38716)
Link 

J. Kissel, H. Radkins, J. Warner, B. Weaver, T. Sadecki

Given the speed at which Jim and Hugh put in Corner 2 and Corner 3 dampers, Jim and I were able to B&K hammer those corners in prep for tuning the smaller Tuned Mass Dampers.

I attach the data from the B&K results, plus a bunch of pictures from the day.

Regarding the B&K results -- remember, we expect that the Blade Srping Dampers will reduce the first bending mode of the blade from ~153 to ~139 Hz. We see exactly that again here in HAM2. However, while the resonance is clear in Corner 3, the feature looks not-so-clear in Corner 2. 

I'm confident this is due to the orientation of the accelerometer: we weren't able to find the same mounting plate that we used in 2016 (see pics from LHO aLOG 26488), so we just mounted it directly to the baseplate of stage 1. In doing so, we got lucky with Corner 3 and the Z axis of the accelerometer was well-aligned with vertical. In Corner 2, we were not so lucky (see pg 9 and 10 of attached).

Still, I think it's good enough to confirm that the Corner 2 resonance is where expected, and we'll tune the TMDs accordingly.
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