Ryan Crouch, Rahul Kumar

The assembly, balancing and testing of all 12 HRTS (Ham Relay Triple Suspension) for O5 is now complete. Currently all 12 HRTS has dummy optic installed at the bottom stage and once the mirrors are ready (with prisms bonded) then it will be replaced (later this year). I am attaching several pictures from the lab which shows all 12 HRTS staged on the optical bench. Later, six of the suspensions will be transported to LLO.

This plot compares the of transfer function performance of all 12 HRTS for all 6 degrees of freedom. We are still analyzing this data and there is scope for improving a couple of them (especially highlighted in green trace). Sometimes, it is as simple as adjusting the flag position wrt to LED/PD in bosems, and other times further fine tuning the balance and alignment of the blade springs.

The final two HRTS which were assembled by us are of OM0 configuration. This has bottom mass (M3 stage) actuation using AOSEM standoff assembly (as per D2300180_v2) as shows in the picture over here. The magnets used at M3 stage is 2.0 mm D x 0.5 mm T, SmCo. The transfer function results for both the OM0 configurations are as follows - attachment01 and attachment02. Both of them look healthy, when compared with the model.

Given below are the OLC, offsets and gains of the bosems attached to OM0 sn02,