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MIF (ITF Control)

yoichi.aso - 21:07 Wednesday 15 September 2021 (18270)

POS table inspection

I checked the optical table at POS today.

I did not find any particular point to worry about at this moment.

I took pictures of the table to record the beam spot positions on the mirrors.

https://photos.app.goo.gl/GYMooxzurdn4NUaX6

I will compute the separation between the green and IR beams to see if the current green beam positions are OK or not.

Note that the beam shutter is currently locked (disabled). You cannot change the state from MEDM. You need to turn the key on the controller box on the POS table to unlock it. Also there is a beam dump behind the shutter. You need to remove it to actually inject the green beam into the chamber.

Comments to this report:

yoichi.aso - 9:10 Thursday 16 September 2021 (18274)

Here is a ray-tracing result of the POS beams.

At the POS table periscope, the separation between the green beam and the backward IR beam is about 60mm.

The current positions of the green beam on the periscope mirrors are shifted to right, which is the correct direction.
However, the amount of shift may not be enough.

When adjusting the green beam path, we should adjust this first.

Images attached to this comment