Muon PDT (All)

 Plots for the central muon drift chambers.

 N
 -----
 The number of PDT hits per event.

 Layer
 -----
 Layer 0 is A-layer. layer 1 and 2 are B and C layers.

 Octant
 ------
 Integrated over layer. The reason octants 0 and 3 are highest 
 is that the A-layer chambers span 2 octants (0+7 and 3+4) because 
 of their large size. These are 013, 023, 033, 010, 020, ans 030.
 The A-layer has the most hits.  

 Y vs Z
 ------
 Occupancy. The units are CM. +Y is up. +Z is South. +X is East.

 X vs Z
 ------
 Occupancy.

 Y vs X
 ------
 Occupancy.

 DDist
 -----
 Drift distance in cm.  I gather that the spikes at 0 and 5 cm are 
 from times that convert to negative distance or off the edge of the 
 cell and are put on the wire or at the edge of the cell.

 DTime
 -----
 Drift time in ns.