Plots of the magnetic field of OAFM
========================================================
for three cases a from the Tosca calculations by 
Felix Bergsma.

a)   Pole gap  800 mm, hole in shielding plates  400x 400mm2
b)   Pole gap 1500 mm, hole in shielding plates  950x 950mm2
c)   Pole gap 1500 mm, hole in shielding plates 2000x2000mm2

for technical reasons the shielding plate configuration is
always SYMMETRIC. Thus we need to combine e.g. (b) for the
upstream and (c) for the downstream part.
Far out side the element size is rather large and can produce
some artefacts.

The units in the plots are m and gauss, the origen is in the
magnet centre, z is the beam direction, y is vertical, and x
horizontal. Bmod is the absolut value of the field.

plots:
 
                                          gap    shield
 1) Bmod, 10*Bmod   -4   to  1.5 m  z     800       400
 2) Bmod, 10*Bmod   -4   to -1.5 m  z
 3) Bmod            -1.5 to  0   m  z
 4) Bmod            -1.5 to  1.5 m  z
 5) Bmod            -1.5 to  1.5 m  x
 6) Bmod            special path for slow proton in 
                            scintillator barrel (sascha)

 7) Bmod            -4   to  1.5 m  z   1500      950
 8) Bmod, 10*Bmod   -4   to -1.5 m  z
 9) Bmod            -1.5 to  0   m  z
10) Bmod            -1.5 to  1.5 m  z
 
11) Bmod            -4   to  1.5 m  z   1500     2000
12) Bmod             0   to  1.5 m  z
13) Bmod          -1.5   to  1.5 m  z

14) Bmod          -3.0   to  3.0 m  z   1500     various
15) Bmod          -3.0   to  3.0 m  z   1500     various

The ps files are loctaed on cernsp in ~gkm/public/opera/
or on axhyp1 in /us0/www/html/compass/tech-board/plots/field/

c18, c19, and c20 correspond to cases a),b), and c)

Gerd