: beginning of operations with laser tracker.
We attach the portable laser head on the opposite side of the primary and we shine it on the flat mirror attached to the bar at the center of the AGW.
We rotate the LUCI rotator at 90° steps and we take the 4 points. The center of the 4 points is the center of the rotator. We move the laser spot here.
Now we check the reflected spot on the dome wall. We try to null the spot wobble at the 360° rotation of the rotator.
In the end we find out that we can tilt the flat mirror at 0.01mm resolution. Considering that this is a 50mm mirror we get an angular resolution of 0.2mrad (~1') that means we cannot reduce the circle on the wall to a diamter < 5mm...
At this point we slided in the dichroic and the fold mirror. We mounted the bracket on the dichroic cart, holding a 45° flat mirror in front of it. We removed the portable laser from its mount on the primary cell and we mounted it on a magnetic pillar fixed to the SX table.
The laser then is shined from the table to the 45° mirror on the flat mirror on the AGW and then back to the laser itself. Anyhow part of the radiation is first reflected by the dichroic, sent to the fold mirror and then to the table. This beam identifies the rotator axis on the table. We put our reference post on it and adjusted the fold mirror in such a way to get it properply in place.
At the end of the operations a serie of clamps have been screwed to the table to mark the reference position for the SX-LGSW.
- 13 May 2015