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AOS (Baffles & Beam dumps)

naoatsu.hirata - 0:20 Monday 26 July 2021 (17635)

Breadboard height

With Yano-san,

On July 21th, We measured height of PR2 and PRM breadboard in more detail.

PR2

First, we removed Mid-size baffle and released PR2 breadboard. We set laser leveler at nominal height(=PR2 mirror center), and measured the distance between breadboard surface and laser leveler.

Around HR side Mid-size baffle, the distance was about 390mm. Around green laser steering mirror, the distance was 386mm.(see attached pic1)

We also measured the distance between the breadboard and the center of green laser steering mirror. It was 380.5mm.(pic2)

PRM

The distance was about 381.5～382.3mm.(pic3)

Non-image files attached to this report

Comments to this report:

naoatsu.hirata - 22:45 Monday 26 July 2021 (17649)

With Akutsu-san and Yano-san,

Today we confirmed height of PR2 breadboard.

This time we set laser leveler at AR side, and use it all measurement.

We started measurement after recovering green beam.

The result was attached. (Pic.1)

HR side were 389.5mm and 390.3mm. AR side were 385.5mm and 386.5mm.

Green beam is aligned with laser leveler. (Pic.2, Pic.3)

We checked tilt of breadboard by some kinds of bubble level. (Pic.4, Pic.5)

Images attached to this comment

Non-image files attached to this comment

Pic1 PR2 breadboard measured 210726.pdf

tomotada.akutsu - 2:15 Tuesday 27 July 2021 (17650)

According to Hirata-san, the red beams from two laser levels were set to illuminate pen lines marked at flanges in the +X and -X directions of the PR2 chamber. The PR2 mirror has been set to the same height with these pen lines. The green beam was also injected into the central poinnt of PR2, which was determined in this manner. So this is the way to practically determine the "beam line height" here. I'm not sure how to treat 1/300 thing here, but considering the situation, this "nominal" beam height should be that of at the HR side of PR2, so the beam height at the AR side (or particulary putting, the beam spot on the invac POP-POM mirror) should go up in +1/300.