uniform field region

[Jim Stewart <jstewart@jlab.org>]

Hello Yang, Franz, and Co.

I am trying to think how to summarize our specification on the field 
uniformity in the clearest most general way. I propose making a drawing 
like what is attached, and then specifying that for any two points 
inside the hatched area that are less than 100 mm apart the difference 
in field must be less than 3 parts in 10^4, and that the uniformity over 
the whole hatched region must be better than 1%.

If I go in from the pole by 70mm my uniformity is only 3 parts in 10^4 
and not 1 part in 10^4. Do other people agree with this? How far in from 
the effective field boundary should we go and what uniformity does this 
correspond to ?

Jim

uniform region-Model.pdf