[dsg-hallb_rich] [EXTERNAL] Re: d0 results for mirrors 5 and 5C

[Marco Contalbrigo]

Dar Tayler,
thank you. The fit shows that your initial choice is
good enough. The fluctuations around the minimum
signal some instability, possibly related to the
time of measurement. What is the typical sequence
(do you take the central first, and then one side
at a time) ? May you repeat the best measurement
more than once, e.g. at beginning and end ?
Thanks, Marco.

On Wed, 29 Sep 2021, Tyler Lemon wrote:

> Hi Marco Mirazita and Marco Contalbrigo,
> 
> Over the past two days, Mindy, Aaron, and I took d0 measurements on RICH spherical mirrors 5 and 5C.
> 
> After our meeting this morning, I was able to get the program that fits the d0 vs Z curve. Attached are the
> results as PDFs.
> 
> The table below has the fit value and also the radius of curvature from determined by the program.
> 
> Mirror
> Position
> Fit d0 [mm]
> Fit Z [mm]
> 5
> horizontal
> 1.98
> 2710.21
> 5
> vertical
> 2.29
> 2703.53
> 5C
> horizontal
> 2.26
> 2708.40
> 5C
> vertical
> 3.31
> 2700.78
> 
> 
> As we discussed in the meeting today, we'll take additional sets of d0 measurements after trying to limit the
> background light noise in the room and taking multiple background measurements.
> 
> -Tyler
> 
>