0 :TRACK     : track number
   1 :NFILE     : 
   2 :PTOT      : 
   3 :PTHETA    : 
   4 :PPHI      : 
   5 :R_VERTEX  : 
   6 :Z_VERTEX  : event vertex
   7 :THET_VER  : 
   8 :PHI_VER   : 
   9 :ITPARENT  : 
  10 :IDPARENT  : 
  11 :IDPART    : 
  12 :ITORIGIN  : 
  13 :IDORIGIN  : 
  14 :IHIT      : 
  15 :LAYER     : 1-4 is the barrel, 5-8 is the South endcaps, 9-12 the North endcaps 
  16 :THETA     : 
  17 :PHI       : 
  18 :XGLOBAL   : global x coordinate
  19 :YGLOBAL   : global y coordinate
  20 :ZGLOBAL   : global z coordinate
  21 :PMOMX     : 
  22 :PMOMY     : 
  23 :PMOMZ     : 
  24 :IPC123    : 
  25 :PC1THETA  : 
  26 :PC1PHI    : 
  27 :PC1RDIST  : 
  28 :PC1ZDIST  : 
  29 :PC2THETA  : 
  30 :PC2PHI    : 
  31 :PC2RDIST  : 
  32 :PC2ZDIST  : 
  33 :PC3THETA  : 
  34 :PC3PHI    : 
  35 :PC3RDIST  : 
  36 :PC3ZDIST  : 
  37 :DELE      : energy deposited
  38 :XLOCIN    : local x inside silicon for track entry point
  39 :YLOCIN    : local y inside silicon
  40 :ZLOCIN    : local z inside silicon
  41 :XLOCOUT   : local x inside silicon for track exit point
  42 :YLOCOUT   : local x inside silicon
  43 :ZLOCOUT   : local x inside silicon
  44 :HITVOL0   : 
  45 :HITVOL1   : 
  46 :HITVOL2   : 
  47 :HITVOL3   : 
  48 :HITVOL4   : 
  49 :HITVOL5   : 
  50 :NHIT      : 
  51 :X0_EVENT  : 
  52 :Y0_EVENT  : 
  53 :Z0_EVENT  : 
  54 :B_IMPACT  : 
  55 :EVENT     : event number

root [4] AncSvx->Draw("ZGLOBAL:YGLOBAL") produces this picture: This file contained 11 central AuAu events, and you can see the silicon barrels, as well as the 4 LDRD endcap planes in the tilted configuration. You can see that these consist of 12, 20, 20, 20 silicon modules, staggered front-back.
This shows that when we look at the bottom module of the the first endcap plane (layer 9), that this is a silicon plane about 7cm wide and 6mm high, and that there are 32 track entry points in event 3.