Exit End field free region alignment  Runs 21-23
x and y = 0 is at stored beam location, z = 0 is the middle of second block.  
Exit end of 3rd block z = 216.4 mm, exit of nose and end of mirror plate z = 279.5 mm.  

Each block is 144.272 mm in length, 1/2 block is 72.136 mm
3 blocks together at 432.816 mm, 1/2 = 216.4 mm (this is the distance to the center of the second block from the end of the pole)

Nose piece is 63.5 mm in length, so middle of second block is 279.9 mm from nose piece end.

Measurement points in other blocks are 76.2 mm from entrannce (1st block) and exit (3rd block) which translates to +/- 140.21 mm  from center of 2nd block.

25 mm from 3rd block exit is 191.4 from 2nd block center.  The scan will start at 191.5 mm

Entrance End field free region alignment.  This is the alignment with the Y pole.   Runs 24- 

Used Matlab function B9V4_Ypath2.m to calculate hall probe positions for scan.  

 The distance from the centerline to the middle of the y pole at the pole
% entrance is 0.089461 m, the pole is 1.5 " wide (0.0381 m). The angle of
% the pole is 8.792 degrees to the vertex.  
% and the distance from the angle origin to the middle of the pole at the
% entrance is 0.58480 m (23.026' - tand(6.9146)*0.75" = 0.58480 m)
 
% The two scans need to be made, one 25 mm into the entrance pole then
% extending back out of the magnet until the field reaches 1 G. 25 mm from 3rd block exit is 191.4 from 2nd block center.  The scan will start at 190 mm 
% The second scan is at the approximate middle of one of the curves of the y pole.  The middle of the 2nd block is used as the origin and is at 0.2164 from the 1st block entrance.
% Measurement points in other blocks are 76.2 mm from entrance (1st block) and exit (3rd block) which translates to +/- 0.14021 m  from center of 2nd block.
 
 
% To calculate the y coordinates from z coordinate using middle of 2nd block as origin two angle are used.  For the 1st scan (out of the magnet) the angle 8.792 degrees was used to make a line
% perpedicular to the entrance pole face.  The acros the poe scans use a
% line that goes from the middle of the y pole entrance to a point 0.75"
% offset in y from the centerline of the magnet.  This line uses a line offset 0.75" above the centerline from middle of
% pole at entrance to 0.75" above centerline at the vertex. To calculating the angle: opposite = 3.522" - 0.75" = 2.7721" = 0.07074114 m; hypotinuse = 23.026" - tand(6.9146)*0.75" = 0.58480 m
% approximately in the center of the curved pole and has an angle of theta = asind(0.0704114/ 0.58486) = 6.9146 degrees.  For z scan across pole scan of magnet.  
% Both angles have a z origin is at the y pole vertex which is at Z = -0.368392 m from 2nd block center.  Center of the 2nd block is 216.4 mm in from entrance end. 
% Z Origin for angles calculated are at Z = -0.368392 m  (0.58480 - 0.216408 = 0.368392 m ) from 2nd block center.