[Clas12_rich] RICH Mirror CMM analysis summary for mirror surface

[Tyler Lemon]

Hello,

We have analyzed the mirror surface of mirrors C2, C3, C4, and C5. The results are attached.

Within the attached document there is a diagram from a presentation shared on the mirrors. The diagram denotes the naming scheme used for the sides of mirrors and their corners. The name of the mirror, "C5" for example, is written in black. On Mirror C5, the sides are denoted in red as Right, Top, Left, and Bottom. The corners are denoted in blue as A, B, C, and D.

There are tables containing the CMM length measurements, the specified lengths, and the difference between specified length and CMM measurements. For Table 1, the radius of curvature has been determined using the Python program that Brian shared. On Table 3, any side where the difference between specified length and CMM measured length is greater than the 1 [mm] tolerance has its cell highlighted.

The graphs were created by Mary Ann to help visualize which sides have dimensions that fit within the 1 [mm] tolerance. The difference between specified length and CMM measurements for each side and diagonal is plotted in blue with the CMM measurement error shown by the error bars. The 1 [mm] tolerance is shown by the horizontal red line.

After discussion, we have reached the following conclusions:
1. Mirror C5 is the only mirror where all dimensions are within the 1 [mm] tolerance. All other sides have at least one dimension that is not in the 1 [mm] tolerance.
2. Mirror C4's left side is the furthest out of tolerance with ~3.8 [mm] difference between the CMM measurement and specified value. This is more evident in Mary Ann's graph for C4.

There are also questions we have:
1. Is it more critical if according to the CMM measurements, the mirrors are smaller or bigger than the specified dimensions? Since the differences in table 3 were found by subtracting specified value from CMM measured value, value in    this table that is positive means that the mirror is smaller than specified. Is this as big of a problem as if the mirror is too big?
2. What would be the plan or procedure in order to compensate for the mirrors that fall out of the 1 [mm] tolerance?

Hopefully we can discuss these points when we meet tomorrow.

Best regards,
Tyler
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