| In Pisa displays, there often appeared these mysterious large spheres in the North and South walls. These turn out to be the endcaps of the DX magnets, which are defined as a 1/4" steel sections of a shell with opening angle theta = ±30°. Geant3 cannot draw just the defined portions, so it draws the whole sphere. | 
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| I replaced the sphere with a polycone, which is a good
approximation, and does not have display problems.
Note this new endcap (red) has no opening in it where the beam pipe (light blue) connects. In the past, this was also the case for the sphere. That means in effect that up to now, 1/4" of steel was sitting in the beampipe. Files affected: muident.f, phnx.par. | 
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| To clear the central, off-center part of the encap, I split it into 2 parts EDXM (black) and EDXN (red), where EDXM starts at r=0, and EDXN has an inner radius cutout to just clear the square cutout of mother volume MUHL. | 
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| This arrangement minimizes the number of volume overlaps. Only
DXTF (light blue) extrudes from MUHL square interior hole (turquoise).
The turquoise square
opening is just big enough to allow for the beam pipe (not shown).
In the past, the DX magnet volume had no central hole, so the beampipe volumes just intruded into it. | 
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