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Payload (Payload)

Majorana Montani Naticchioni Perciballi Piegiovanni Travasso Vocca - 20:43 Tuesday 08 June 2021 (52076)

First suspension of LM dummy mirror with FUSED SILICA suspension

This morning the planes of the top platform and that of the maiornette were carefully levelled horizonally. In the afternoon the dummy mirror (105 kg) with actual ears and 640 um diameter fibers was suspended. We also tested the procedure to safely install the lateral parts of the cage and the craddle. In the final installation the Ti craddle will initially be a part of the mirror box / then it is used (as we did here) as a jack to insert precisely the mirror under the marionette / and finally, after the fiber installation and release of the mirro load on the anchors, as a part of the cage. We thank EGO support for mechanics and assistance. We leave the system loaded.

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majorana - 20:37 Wednesday 09 June 2021 (52097)

We suspended the double pendulum Marionette+ Mirror(Dummy). Note that the inner radius of the mirror is 350 mm. like the present AdV mirrors.

The mirrror suspension through fibers was not optimal, meaning that the marionette and the mirror cylinder are not pperfeectly parallel. A pitch mislaignment of 11 mrad upwards is present (our standar target is 1 +-mrad). We expected it. Anyhow yestedray we decided to postpone the optimization becuse that can be recovered by swapping the position of two fibers, while we had to validate the assembly milestone.

Today we released the marionette and balanced it. We have nice pitch at 56 mHz and roll at 40 MHz. We leave the system suspended, both mario and mirror.

Next week we fix the alignment Mario/Mirror. It must be done before dressing the bottom part of the cage.

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